Bug 1253426 - When Fennec is brought to the foreground, soft keyboard needs to be restored if it was previously visible r=snorp

mobile/android/base/java/org/mozilla/gecko/GeckoInputConnection.java

@@ -473,6 +473,8 @@ class GeckoInputConnection
         return mEditableClient.setInputConnectionHandler(getBackgroundHandler());
     }
 
+    private boolean mIsVisible = false;
+
     @Override
     public InputConnection onCreateInputConnection(EditorInfo outAttrs) {
         if (mIMEState == IME_STATE_DISABLED) {
@@ -585,6 +587,13 @@ class GeckoInputConnection
         Editable editable = getEditable();
         outAttrs.initialSelStart = Selection.getSelectionStart(editable);
         outAttrs.initialSelEnd = Selection.getSelectionEnd(editable);
+
+        if (mIsVisible) {
+            // The app has been brought to the foreground and the Soft Keyboard
+            // was previously visible, so request that it be shown again.
+            showSoftInput();
+        }
+
         return this;
     }
 
@@ -790,6 +799,16 @@ class GeckoInputConnection
         return processKey(KeyEvent.ACTION_UP, keyCode, event);
     }
 
+    @Override
+    public void onWindowVisibilityChanged (int visibility) {
+        if (visibility == View.VISIBLE) {
+            mIsVisible = true;
+        } else {
+            mIsVisible = false;
+            hideSoftInput();
+        }
+    }
+
     /**
      * Get a key that represents a given character.
      */

mobile/android/base/java/org/mozilla/gecko/GeckoView.java

@@ -343,8 +343,24 @@ public class GeckoView extends LayerView
         }
     }
 
+    private int mLastVisibility = View.GONE;
+
     /* package */ void setInputConnectionListener(final InputConnectionListener icl) {
         mInputConnectionListener = icl;
+        if (mInputConnectionListener != null) {
+            mInputConnectionListener.onWindowVisibilityChanged(mLastVisibility);
+        }
+    }
+
+    @Override
+    protected void onWindowVisibilityChanged (int visibility) {
+        mLastVisibility = visibility;
+
+        if (mInputConnectionListener != null) {
+            mInputConnectionListener.onWindowVisibilityChanged(visibility);
+        }
+
+        super.onWindowVisibilityChanged(visibility);
     }
 
     @Override

mobile/android/base/java/org/mozilla/gecko/InputConnectionListener.java

@@ -21,5 +21,6 @@ interface InputConnectionListener
     boolean onKeyLongPress(int keyCode, KeyEvent event);
     boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event);
     boolean onKeyUp(int keyCode, KeyEvent event);
+    void onWindowVisibilityChanged (int visibility);
     boolean isIMEEnabled();
 }