Fix OSK flickering issue

content/renderer/render_widget.cc

Index: content/renderer/render_widget.cc
diff --git a/content/renderer/render_widget.cc b/content/renderer/render_widget.cc
index 2ece7075add91125890a1c8b7bdfb2b73940e1b4..46b2b75480431ee619f1390b1143b273b6224989 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -498,7 +498,8 @@ RenderWidget::RenderWidget(CompositorDependencies* compositor_deps,
       display_mode_(blink::WebDisplayModeUndefined),
       handling_input_event_(false),
       handling_event_overscroll_(nullptr),
-      handling_ime_event_(false),
+      handling_ime_events_count_(0),
+      pending_show_ime_if_needed_(false),
       handling_event_type_(WebInputEvent::Undefined),
       ignore_ack_for_mouse_move_from_debugger_(false),
       closing_(false),
@@ -517,6 +518,7 @@ RenderWidget::RenderWidget(CompositorDependencies* compositor_deps,
       next_output_surface_id_(0),
 #if defined(OS_ANDROID)
       text_field_is_dirty_(false),
+      pending_update_from_non_ime_(false),
 #endif
       popup_origin_scale_for_emulation_(0.f),
       frame_swap_message_queue_(new FrameSwapMessageQueue()),
@@ -1069,27 +1071,11 @@ void RenderWidget::OnHandleInputEvent(const blink::WebInputEvent* input_event,
       handling_event_overscroll_resetter(&handling_event_overscroll_,
                                          &event_overscroll);
 
-#if defined(OS_ANDROID)
-  // On Android, when a key is pressed or sent from the Keyboard using IME,
-  // |AdapterInputConnection| generates input key events to make sure all JS
-  // listeners that monitor KeyUp and KeyDown events receive the proper key
-  // code. Since this input key event comes from IME, we need to set the
-  // IME event guard here to make sure it does not interfere with other IME
-  // events.
-  scoped_ptr<ImeEventGuard> ime_event_guard_maybe;
-  if (WebInputEvent::isKeyboardEventType(input_event->type)) {
-    const WebKeyboardEvent& key_event =
-        *static_cast<const WebKeyboardEvent*>(input_event);
-    // Some keys are special and it's essential that no events get blocked.
-    if (key_event.nativeKeyCode != AKEYCODE_TAB &&
-        key_event.nativeKeyCode != AKEYCODE_DPAD_CENTER &&
-        key_event.nativeKeyCode != AKEYCODE_DPAD_LEFT &&
-        key_event.nativeKeyCode != AKEYCODE_DPAD_RIGHT &&
-        key_event.nativeKeyCode != AKEYCODE_DPAD_UP &&
-        key_event.nativeKeyCode != AKEYCODE_DPAD_DOWN)
-      ime_event_guard_maybe.reset(new ImeEventGuard(this));
-  }
-#endif
+  const bool is_keyboard_event =
+      WebInputEvent::isKeyboardEventType(input_event->type);
+
+  // For non-keyboard events, we want the change source to be FROM_NON_IME.
+  ImeEventGuard guard(this, !is_keyboard_event);
 
   base::TimeTicks start_time;
   if (base::TimeTicks::IsHighResolution())
@@ -1879,27 +1865,46 @@ static bool IsDateTimeInput(ui::TextInputType type) {
 
 
 void RenderWidget::StartHandlingImeEvent() {
-  DCHECK(!handling_ime_event_);
-  handling_ime_event_ = true;
+  ++handling_ime_events_count_;
 }
 
-void RenderWidget::FinishHandlingImeEvent() {
-  DCHECK(handling_ime_event_);
-  handling_ime_event_ = false;
+void RenderWidget::FinishHandlingImeEvent(bool from_non_ime) {
+  --handling_ime_events_count_;
+  CHECK_GE(handling_ime_events_count_, 0);
+#if defined(OS_ANDROID)
+  // From non-IME source should take precedence because AdapterInputConnection
+  // makes real changes only when it's not originating from IME.
+  pending_update_from_non_ime_ |= from_non_ime;
+#endif
+  if (handling_ime_events_count_ > 0)
+    return;
+
   // While handling an ime event, text input state and selection bounds updates
   // are ignored. These must explicitly be updated once finished handling the
   // ime event.
   UpdateSelectionBounds();
 #if defined(OS_ANDROID)
-  UpdateTextInputState(NO_SHOW_IME, FROM_IME);
+  UpdateTextInputState(NO_SHOW_IME,
+                       pending_update_from_non_ime_ ? FROM_NON_IME : FROM_IME);
+  pending_update_from_non_ime_ = false;
 #endif
 }
 
 void RenderWidget::UpdateTextInputState(ShowIme show_ime,
                                         ChangeSource change_source) {
   TRACE_EVENT0("renderer", "RenderWidget::UpdateTextInputState");
-  if (handling_ime_event_)
+  if (handling_ime_events_count_ > 0) {
+    if (show_ime == SHOW_IME_IF_NEEDED)
+      pending_show_ime_if_needed_ = true;
+
     return;
+  }
+
+  if (pending_show_ime_if_needed_) {
+    show_ime = SHOW_IME_IF_NEEDED;
+    pending_show_ime_if_needed_ = false;
+  }
+
   ui::TextInputType new_type = GetTextInputType();
   if (IsDateTimeInput(new_type))
     return;  // Not considered as a text input field in WebKit/Chromium.
@@ -1965,7 +1970,7 @@ void RenderWidget::UpdateSelectionBounds() {
   TRACE_EVENT0("renderer", "RenderWidget::UpdateSelectionBounds");
   if (!webwidget_)
     return;
-  if (handling_ime_event_)
+  if (handling_ime_events_count_ > 0)
     return;
 
 #if defined(USE_AURA)