qt: Make askpassphrase dialog behave more sanely

Set minimum sizes appropriately, and make sure that they
are enforced. Replaces #5226.

src/qt/askpassphrasedialog.cpp

@@ -23,6 +23,10 @@ AskPassphraseDialog::AskPassphraseDialog(Mode mode, QWidget *parent) :
 {
     ui->setupUi(this);
 
+    ui->passEdit1->setMinimumSize(ui->passEdit1->sizeHint());
+    ui->passEdit2->setMinimumSize(ui->passEdit2->sizeHint());
+    ui->passEdit3->setMinimumSize(ui->passEdit3->sizeHint());
+
     ui->passEdit1->setMaxLength(MAX_PASSPHRASE_SIZE);
     ui->passEdit2->setMaxLength(MAX_PASSPHRASE_SIZE);
     ui->passEdit3->setMaxLength(MAX_PASSPHRASE_SIZE);
@@ -35,9 +39,9 @@ AskPassphraseDialog::AskPassphraseDialog(Mode mode, QWidget *parent) :
     switch(mode)
     {
         case Encrypt: // Ask passphrase x2
+            ui->warningLabel->setText(tr("Enter the new passphrase to the wallet.<br/>Please use a passphrase of <b>ten or more random characters</b>, or <b>eight or more words</b>."));
             ui->passLabel1->hide();
             ui->passEdit1->hide();
-            ui->warningLabel->setText(tr("Enter the new passphrase to the wallet.<br/>Please use a passphrase of <b>ten or more random characters</b>, or <b>eight or more words</b>."));
             setWindowTitle(tr("Encrypt wallet"));
             break;
         case Unlock: // Ask passphrase
@@ -61,7 +65,6 @@ AskPassphraseDialog::AskPassphraseDialog(Mode mode, QWidget *parent) :
             ui->warningLabel->setText(tr("Enter the old and new passphrase to the wallet."));
             break;
     }
-
     textChanged();
     connect(ui->passEdit1, SIGNAL(textChanged(QString)), this, SLOT(textChanged()));
     connect(ui->passEdit2, SIGNAL(textChanged(QString)), this, SLOT(textChanged()));

src/qt/forms/askpassphrasedialog.ui

@@ -7,7 +7,7 @@
     <x>0</x>
     <y>0</y>
     <width>598</width>
-    <height>198</height>
+    <height>222</height>
    </rect>
   </property>
   <property name="sizePolicy">
@@ -26,8 +26,14 @@
    <string>Passphrase Dialog</string>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
+   <property name="sizeConstraint">
+    <enum>QLayout::SetMinimumSize</enum>
+   </property>
    <item>
     <widget class="QLabel" name="warningLabel">
+     <property name="text">
+      <string notr="true">Placeholder text</string>
+     </property>
      <property name="textFormat">
       <enum>Qt::RichText</enum>
      </property>
@@ -38,6 +44,9 @@
    </item>
    <item>
     <layout class="QFormLayout" name="formLayout">
+     <property name="sizeConstraint">
+      <enum>QLayout::SetMinimumSize</enum>
+     </property>
      <property name="fieldGrowthPolicy">
       <enum>QFormLayout::AllNonFixedFieldsGrow</enum>
      </property>