Bug 1282668 Get rid of nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE r=m_kato

Currently, all widgets request selection change notifications to IMEContentObserver.  Additionally, IMEContentObserver needs to listen selection changes for caching latest selection for eQuerySelectedText.  Therefore, it doesn't make sense to keep defining nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE.

If widgets didn't need selection change notifications, they could just ignore the unnecessary notifications.

Note that all widgets don't need selection change notifications if a plugin has focus and IMEContentObserver cannot observe selection changes in the plugin.  Therefore, if IMEContentObserver is initialized with a plugin, it shouldn't listen selection changes (and doesn't need to notify widgets of selection changes).

MozReview-Commit-ID: FOVFFgA2nOz

--HG--
extra : rebase_source : 3e16d5023835f99f82934e754d2e7db70474f9ee

dom/events/IMEContentObserver.cpp

@@ -351,6 +351,8 @@ IMEContentObserver::InitWithEditor(nsPresContext* aPresContext,
     return false;
   }
 
+  MOZ_ASSERT(!WasInitializedWithPlugin());
+
   return true;
 }
 
@@ -386,9 +388,17 @@ IMEContentObserver::InitWithPlugin(nsPresContext* aPresContext,
     return false;
   }
 
+  MOZ_ASSERT(WasInitializedWithPlugin());
+
   return true;
 }
 
+bool
+IMEContentObserver::WasInitializedWithPlugin() const
+{
+  return mDocShell && !mEditor;
+}
+
 void
 IMEContentObserver::Clear()
 {
@@ -424,8 +434,10 @@ IMEContentObserver::ObserveEditableNode()
   }
 
   mUpdatePreference = mWidget->GetIMEUpdatePreference();
-  if (mUpdatePreference.WantSelectionChange()) {
-    // add selection change listener
+  if (!WasInitializedWithPlugin()) {
+    // Add selection change listener only when this starts to observe
+    // non-plugin content since we cannot detect selection changes in
+    // plugins.
     nsCOMPtr<nsISelectionPrivate> selPrivate(do_QueryInterface(mSelection));
     NS_ENSURE_TRUE_VOID(selPrivate);
     nsresult rv = selPrivate->AddSelectionListener(this);
@@ -494,7 +506,7 @@ IMEContentObserver::UnregisterObservers()
     mEditor->RemoveEditorObserver(this);
   }
 
-  if (mUpdatePreference.WantSelectionChange() && mSelection) {
+  if (mSelection) {
     nsCOMPtr<nsISelectionPrivate> selPrivate(do_QueryInterface(mSelection));
     if (selPrivate) {
       selPrivate->RemoveSelectionListener(this);
@@ -1285,7 +1297,7 @@ IMEContentObserver::UpdateSelectionCache()
 {
   MOZ_ASSERT(IsSafeToNotifyIME());
 
-  if (!mUpdatePreference.WantSelectionChange()) {
+  if (WasInitializedWithPlugin()) {
     return false;
   }
 

dom/events/IMEContentObserver.h

@@ -94,6 +94,7 @@ public:
                          nsIEditor* aEditor);
   bool IsManaging(nsPresContext* aPresContext, nsIContent* aContent) const;
   bool IsManaging(const TextComposition* aTextComposition) const;
+  bool WasInitializedWithPlugin() const;
   bool IsEditorHandlingEventForComposition() const;
   bool KeepAliveDuringDeactive() const
   {
@@ -186,8 +187,7 @@ private:
    * UpdateSelectionCache() updates mSelectionData with the latest selection.
    * This should be called only when IsSafeToNotifyIME() returns true.
    *
-   * Note that this does nothing if mUpdatePreference.WantSelectionChange()
-   * returns false.
+   * Note that this does nothing if WasInitializedWithPlugin() returns true.
    */
   bool UpdateSelectionCache();
 

widget/IMEData.h

@@ -39,7 +39,6 @@ struct nsIMEUpdatePreference final
   enum : Notifications
   {
     NOTIFY_NOTHING                       = 0,
-    NOTIFY_SELECTION_CHANGE              = 1 << 0,
     NOTIFY_TEXT_CHANGE                   = 1 << 1,
     NOTIFY_POSITION_CHANGE               = 1 << 2,
     // NOTIFY_MOUSE_BUTTON_EVENT_ON_CHAR is used when mouse button is pressed
@@ -81,11 +80,6 @@ struct nsIMEUpdatePreference final
     mWantUpdates &= ~DEFAULT_CONDITIONS_OF_NOTIFYING_CHANGES;
   }
 
-  bool WantSelectionChange() const
-  {
-    return !!(mWantUpdates & NOTIFY_SELECTION_CHANGE);
-  }
-
   bool WantTextChange() const
   {
     return !!(mWantUpdates & NOTIFY_TEXT_CHANGE);
@@ -98,7 +92,7 @@ struct nsIMEUpdatePreference final
 
   bool WantChanges() const
   {
-    return WantSelectionChange() || WantTextChange();
+    return WantTextChange();
   }
 
   bool WantMouseButtonEventOnChar() const

widget/PuppetWidget.cpp

@@ -821,7 +821,6 @@ PuppetWidget::GetIMEUpdatePreference()
                                  nsIMEUpdatePreference::NOTIFY_POSITION_CHANGE);
   }
   return nsIMEUpdatePreference(mIMEPreferenceOfParent.mWantUpdates |
-                               nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE |
                                nsIMEUpdatePreference::NOTIFY_TEXT_CHANGE |
                                nsIMEUpdatePreference::NOTIFY_POSITION_CHANGE );
 #else
@@ -897,9 +896,8 @@ PuppetWidget::NotifyIMEOfSelectionChange(
     aIMENotification.mSelectionChangeData.mReversed,
     aIMENotification.mSelectionChangeData.GetWritingMode());
 
-  if (mIMEPreferenceOfParent.WantSelectionChange() &&
-      (mIMEPreferenceOfParent.WantChangesCausedByComposition() ||
-       !aIMENotification.mSelectionChangeData.mCausedByComposition)) {
+  if (mIMEPreferenceOfParent.WantChangesCausedByComposition() ||
+      !aIMENotification.mSelectionChangeData.mCausedByComposition) {
     mTabChild->SendNotifyIMESelection(mContentCache, aIMENotification);
   } else {
     mTabChild->SendUpdateContentCache(mContentCache);

widget/android/nsWindow.cpp

@@ -3369,9 +3369,7 @@ nsWindow::GetIMEUpdatePreference()
     if (GetInputContext().mIMEState.mEnabled == IMEState::PLUGIN) {
       return nsIMEUpdatePreference();
     }
-    return nsIMEUpdatePreference(
-        nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE |
-        nsIMEUpdatePreference::NOTIFY_TEXT_CHANGE);
+    return nsIMEUpdatePreference(nsIMEUpdatePreference::NOTIFY_TEXT_CHANGE);
 }
 
 nsresult

widget/cocoa/nsChildView.mm

@@ -1934,11 +1934,10 @@ nsChildView::ExecuteNativeKeyBinding(NativeKeyBindingsType aType,
 nsIMEUpdatePreference
 nsChildView::GetIMEUpdatePreference()
 {
-  // While a plugin has focus, IMEInputHandler doesn't need any notifications.
-  if (mInputContext.mIMEState.mEnabled == IMEState::PLUGIN) {
-    return nsIMEUpdatePreference();
-  }
-  return nsIMEUpdatePreference(nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE);
+  // XXX Shouldn't we move floating window which shows composition string
+  //     when plugin has focus and its parent is scrolled or the window is
+  //     moved?
+  return nsIMEUpdatePreference();
 }
 
 NSView<mozView>* nsChildView::GetEditorView()

widget/gtk/IMContextWrapper.cpp

@@ -333,7 +333,7 @@ IMContextWrapper::GetIMEUpdatePreference() const
     }
 
     nsIMEUpdatePreference::Notifications notifications =
-        nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE;
+        nsIMEUpdatePreference::DEFAULT_CONDITIONS_OF_NOTIFYING_CHANGES;
     // If it's not enabled, we don't need position change notification.
     if (IsEnabled()) {
         notifications |= nsIMEUpdatePreference::NOTIFY_POSITION_CHANGE;

widget/windows/IMMHandler.cpp

@@ -395,7 +395,6 @@ IMMHandler::GetIMEUpdatePreference()
 {
   return nsIMEUpdatePreference(
     nsIMEUpdatePreference::NOTIFY_POSITION_CHANGE |
-    nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE |
     nsIMEUpdatePreference::NOTIFY_MOUSE_BUTTON_EVENT_ON_CHAR);
 }
 

widget/windows/TSFTextStore.cpp

@@ -4546,7 +4546,6 @@ TSFTextStore::GetIMEUpdatePreference()
     sThreadMgr->GetFocus(getter_AddRefs(docMgr));
     if (docMgr == sEnabledTextStore->mDocumentMgr) {
       nsIMEUpdatePreference updatePreference(
-        nsIMEUpdatePreference::NOTIFY_SELECTION_CHANGE |
         nsIMEUpdatePreference::NOTIFY_TEXT_CHANGE |
         nsIMEUpdatePreference::NOTIFY_POSITION_CHANGE |
         nsIMEUpdatePreference::NOTIFY_MOUSE_BUTTON_EVENT_ON_CHAR |