Add workaround for occasionally buggy header loading code

If custom headers (block identifying headers and DNT) are not being
used, we call super. This way, if the user turns on those options and
experiences problems on a site, they can turn off the option so that the
site works correctly.

app/src/main/java/acr/browser/lightning/view/LightningWebClient.java

@@ -101,7 +101,7 @@ public class LightningWebClient extends WebViewClient {
             mLightningView.getTitleInfo().setTitle(view.getTitle());
         }
         if (Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT &&
-                mLightningView.getInvertePage()) {
+            mLightningView.getInvertePage()) {
             view.evaluateJavascript(Constants.JAVASCRIPT_INVERT_PAGE, null);
         }
         mUIController.tabChanged(mLightningView);
@@ -139,24 +139,24 @@ public class LightningWebClient extends WebViewClient {
         builder.setTitle(mActivity.getString(R.string.title_sign_in));
         builder.setView(passLayout);
         builder.setCancelable(true)
-                .setPositiveButton(mActivity.getString(R.string.title_sign_in),
-                        new DialogInterface.OnClickListener() {
-                            @Override
-                            public void onClick(DialogInterface dialog, int id) {
-                                String user = name.getText().toString();
-                                String pass = password.getText().toString();
-                                handler.proceed(user.trim(), pass.trim());
-                                Log.d(Constants.TAG, "Request Login");
-
-                            }
-                        })
-                .setNegativeButton(mActivity.getString(R.string.action_cancel),
-                        new DialogInterface.OnClickListener() {
-                            @Override
-                            public void onClick(DialogInterface dialog, int id) {
-                                handler.cancel();
-                            }
-                        });
+            .setPositiveButton(mActivity.getString(R.string.title_sign_in),
+                new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        String user = name.getText().toString();
+                        String pass = password.getText().toString();
+                        handler.proceed(user.trim(), pass.trim());
+                        Log.d(Constants.TAG, "Request Login");
+
+                    }
+                })
+            .setNegativeButton(mActivity.getString(R.string.action_cancel),
+                new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        handler.cancel();
+                    }
+                });
         AlertDialog alert = builder.create();
         alert.show();
 
@@ -169,7 +169,7 @@ public class LightningWebClient extends WebViewClient {
     @Override
     public void onScaleChanged(@NonNull final WebView view, final float oldScale, final float newScale) {
         if (view.isShown() && mLightningView.mPreferences.getTextReflowEnabled() &&
-                Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {
+            Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {
             if (mIsRunning)
                 return;
             if (Math.abs(mZoomScale - newScale) > 0.01f) {
@@ -223,26 +223,26 @@ public class LightningWebClient extends WebViewClient {
             stringBuilder.append(" - ").append(mActivity.getString(messageCode)).append('\n');
         }
         String alertMessage =
-                mActivity.getString(R.string.message_insecure_connection, stringBuilder.toString());
+            mActivity.getString(R.string.message_insecure_connection, stringBuilder.toString());
 
         AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
         builder.setTitle(mActivity.getString(R.string.title_warning));
         builder.setMessage(alertMessage)
-                .setCancelable(true)
-                .setPositiveButton(mActivity.getString(R.string.action_yes),
-                        new DialogInterface.OnClickListener() {
-                            @Override
-                            public void onClick(DialogInterface dialog, int id) {
-                                handler.proceed();
-                            }
-                        })
-                .setNegativeButton(mActivity.getString(R.string.action_no),
-                        new DialogInterface.OnClickListener() {
-                            @Override
-                            public void onClick(DialogInterface dialog, int id) {
-                                handler.cancel();
-                            }
-                        });
+            .setCancelable(true)
+            .setPositiveButton(mActivity.getString(R.string.action_yes),
+                new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        handler.proceed();
+                    }
+                })
+            .setNegativeButton(mActivity.getString(R.string.action_no),
+                new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        handler.cancel();
+                    }
+                });
         builder.create().show();
     }
 
@@ -251,21 +251,21 @@ public class LightningWebClient extends WebViewClient {
         AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
         builder.setTitle(mActivity.getString(R.string.title_form_resubmission));
         builder.setMessage(mActivity.getString(R.string.message_form_resubmission))
-                .setCancelable(true)
-                .setPositiveButton(mActivity.getString(R.string.action_yes),
-                        new DialogInterface.OnClickListener() {
-                            @Override
-                            public void onClick(DialogInterface dialog, int id) {
-                                resend.sendToTarget();
-                            }
-                        })
-                .setNegativeButton(mActivity.getString(R.string.action_no),
-                        new DialogInterface.OnClickListener() {
-                            @Override
-                            public void onClick(DialogInterface dialog, int id) {
-                                dontResend.sendToTarget();
-                            }
-                        });
+            .setCancelable(true)
+            .setPositiveButton(mActivity.getString(R.string.action_yes),
+                new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        resend.sendToTarget();
+                    }
+                })
+            .setNegativeButton(mActivity.getString(R.string.action_no),
+                new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        dontResend.sendToTarget();
+                    }
+                });
         AlertDialog alert = builder.create();
         alert.show();
     }
@@ -280,18 +280,52 @@ public class LightningWebClient extends WebViewClient {
 
         Map<String, String> headers = mLightningView.getRequestHeaders();
 
-        if (mLightningView.isIncognito() && Utils.doesSupportHeaders()) {
-            view.loadUrl(url, headers);
-            return true;
-        }
-        if (url.startsWith("about:") && Utils.doesSupportHeaders()) {
-            view.loadUrl(url, headers);
-            return true;
+        // If the headers are empty, the user has not expressed the desire
+        // to use them and therefore we can revert back to the old way of loading
+        if (headers.isEmpty()) {
+            if (mLightningView.isIncognito()) {
+                // If we are in incognito, immediately load, we don't want the url to leave the app
+                return super.shouldOverrideUrlLoading(view, url);
+            }
+            if (url.startsWith("about:")) {
+                // If this is an about page, immediately load, we don't need to leave the app
+                return super.shouldOverrideUrlLoading(view, url);
+            }
+
+            if (isMailOrIntent(url, view) || mIntentUtils.startActivityForUrl(view, url)) {
+                // If it was a mailto: link, or an intent, or could be launched elsewhere, do that
+                return true;
+            }
+        } else {
+            if (mLightningView.isIncognito() && Utils.doesSupportHeaders()) {
+                // If we are in incognito, immediately load, we don't want the url to leave the app
+                view.loadUrl(url, headers);
+                return true;
+            }
+            if (url.startsWith("about:") && Utils.doesSupportHeaders()) {
+                // If this is an about page, immediately load, we don't need to leave the app
+                view.loadUrl(url, headers);
+                return true;
+            }
+
+            if (isMailOrIntent(url, view) || mIntentUtils.startActivityForUrl(view, url)) {
+                // If it was a mailto: link, or an intent, or could be launched elsewhere, do that
+                return true;
+            } else if (Utils.doesSupportHeaders()) {
+                // Otherwise, load the headers.
+                view.loadUrl(url, headers);
+                return true;
+            }
         }
+        // If none of those instances was true, revert back to the old way of loading
+        return super.shouldOverrideUrlLoading(view, url);
+    }
+
+    private boolean isMailOrIntent(@NonNull String url, @NonNull WebView view) {
         if (url.startsWith("mailto:")) {
             MailTo mailTo = MailTo.parse(url);
             Intent i = Utils.newEmailIntent(mailTo.getTo(), mailTo.getSubject(),
-                    mailTo.getBody(), mailTo.getCc());
+                mailTo.getBody(), mailTo.getCc());
             mActivity.startActivity(i);
             view.reload();
             return true;
@@ -316,10 +350,6 @@ public class LightningWebClient extends WebViewClient {
                 return true;
             }
         }
-
-        if (!mIntentUtils.startActivityForUrl(view, url) && Utils.doesSupportHeaders()) {
-            view.loadUrl(url, headers);
-        }
-        return Utils.doesSupportHeaders() || super.shouldOverrideUrlLoading(view, url);
+        return false;
     }
 }