[WIP Approach 1] Straighten up input method reactivation

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 57bb2085f61e3f419307f96fb827956bc7ba7206..d8509dea2ed5422c1ca2b0cc3654505fb1f38769 100644
--- a/content/renderer/render_widget.cc
+++ b/content/renderer/render_widget.cc
@@ -221,6 +221,7 @@ RenderWidget::RenderWidget(CompositorDependencies* compositor_deps,
       display_mode_(blink::WebDisplayModeUndefined),
       ime_event_guard_(nullptr),
       ime_in_batch_edit_(false),
+      ime_ignore_until_acked_(false),
       closing_(false),
       host_closing_(false),
       is_swapped_out_(swapped_out),
@@ -270,6 +271,9 @@ RenderWidget::~RenderWidget() {
   // If we are swapped out, we have released already.
   if (!is_swapped_out_ && RenderProcess::current())
     RenderProcess::current()->ReleaseProcess();
+
+  for (size_t i = 0; i < ime_messages_to_send_after_update_.size(); ++i)
+    delete ime_messages_to_send_after_update_[i];
 }
 
 // static
@@ -895,6 +899,22 @@ void RenderWidget::SetInputHandler(RenderWidgetInputHandler* input_handler) {
   DCHECK(!input_handler_);
 }
 
+void RenderWidget::CancelComposition() {
+  ImeEventGuard guard(this);
+  ime_ignore_until_acked_ = true;
+  ime_messages_to_send_after_update_.push_back(
+      new InputHostMsg_ImeCancelComposition(routing_id()));
+}
+
+void RenderWidget::OnFocusedNodeChanged(bool is_editable,
+                                        const gfx::Rect& node_bounds) {
+  ImeEventGuard guard(this);
+  ime_ignore_until_acked_ = true;
+  ime_messages_to_send_after_update_.push_back(
+      new ViewHostMsg_FocusedNodeChanged(
+          routing_id(), is_editable, node_bounds));
+}
+
 void RenderWidget::UpdateTextInputState(ShowIme show_ime,
                                         ChangeSource change_source) {
   TRACE_EVENT0("renderer", "RenderWidget::UpdateTextInputState");
@@ -925,7 +945,7 @@ void RenderWidget::UpdateTextInputState(ShowIme show_ime,
       (IsUsingImeThread() && change_source == ChangeSource::FROM_IME) ||
       (text_input_type_ != new_type || text_input_mode_ != new_mode ||
        text_input_info_ != new_info ||
-       can_compose_inline_ != new_can_compose_inline)
+       can_compose_inline_ != new_can_compose_inline) || ime_ignore_until_acked_
 #if defined(OS_ANDROID)
       || text_field_is_dirty_
 #endif
@@ -948,8 +968,12 @@ void RenderWidget::UpdateTextInputState(ShowIme show_ime,
     params.is_non_ime_change =
         (change_source == ChangeSource::FROM_NON_IME) || text_field_is_dirty_;
     params.batch_edit = ime_in_batch_edit_;
-    if (params.is_non_ime_change)
+    if (ime_ignore_until_acked_ ||
+        (!IsUsingImeThread() && params.is_non_ime_change)) {
+      params.requires_ack = true;
       OnImeEventSentForAck(new_info);
+      ime_ignore_until_acked_ = false;
+    }
     text_field_is_dirty_ = false;
 #endif
     Send(new ViewHostMsg_TextInputStateChanged(routing_id(), params));
@@ -960,6 +984,11 @@ void RenderWidget::UpdateTextInputState(ShowIme show_ime,
     can_compose_inline_ = new_can_compose_inline;
     text_input_flags_ = new_info.flags;
   }
+
+  for (size_t i = 0; i < ime_messages_to_send_after_update_.size(); ++i)
+    Send(ime_messages_to_send_after_update_[i]);
+
+  ime_messages_to_send_after_update_.clear();
 }
 
 bool RenderWidget::WillHandleGestureEvent(const blink::WebGestureEvent& event) {
@@ -1402,7 +1431,7 @@ void RenderWidget::OnImeSetComposition(
     // If we failed to set the composition text, then we need to let the browser
     // process to cancel the input method's ongoing composition session, to make
     // sure we are in a consistent state.
-    Send(new InputHostMsg_ImeCancelComposition(routing_id()));
+    CancelComposition();
   }
   UpdateCompositionInfo(false /* not an immediate request */);
 }
@@ -1635,8 +1664,6 @@ bool RenderWidget::ShouldHandleImeEvent() {
 #if defined(OS_ANDROID)
   if (!GetWebWidget())
     return false;
-  if (IsUsingImeThread())
-    return true;
 
   // We cannot handle IME events if there is any chance that the event we are
   // receiving here from the browser is based on the state that is different
@@ -1759,11 +1786,9 @@ void RenderWidget::OnImeEventGuardFinish(ImeEventGuard* guard) {
   // are ignored. These must explicitly be updated once finished handling the
   // ime event.
   UpdateSelectionBounds();
-#if defined(OS_ANDROID)
   UpdateTextInputState(
       guard->show_ime() ? ShowIme::IF_NEEDED : ShowIme::HIDE_IME,
       guard->from_ime() ? ChangeSource::FROM_IME : ChangeSource::FROM_NON_IME);
-#endif
 }
 
 void RenderWidget::GetSelectionBounds(gfx::Rect* focus, gfx::Rect* anchor) {
@@ -1953,8 +1978,9 @@ void RenderWidget::resetInputMethod() {
   if (text_input_type_ != ui::TEXT_INPUT_TYPE_NONE) {
     // If a composition text exists, then we need to let the browser process
     // to cancel the input method's ongoing composition session.
-    if (GetWebWidget()->finishComposingText(WebWidget::DoNotKeepSelection))
-      Send(new InputHostMsg_ImeCancelComposition(routing_id()));
+    if (GetWebWidget()->finishComposingText(WebWidget::DoNotKeepSelection)) {
+      CancelComposition();
+    }
   }
 
   UpdateCompositionInfo(false /* not an immediate request */);