Some touch-event forwarding optimization.

content/browser/renderer_host/render_widget_host.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/renderer_host/render_widget_host.h"
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
@@ skipping 85 matching lines @@
       is_unresponsive_(false),
       in_flight_event_count_(0),
       in_get_backing_store_(false),
       view_being_painted_(false),
       ignore_input_events_(false),
       text_direction_updated_(false),
       text_direction_(WebKit::WebTextDirectionLeftToRight),
       text_direction_canceled_(false),
       suppress_next_char_events_(false),
       pending_mouse_lock_request_(false),
+      has_touch_handler_(false),
       ALLOW_THIS_IN_INITIALIZER_LIST(weak_factory_(this)) {
   if (routing_id_ == MSG_ROUTING_NONE) {
     routing_id_ = process_->GetNextRoutingID();
     surface_id_ = GpuSurfaceTracker::Get()->AddSurfaceForRenderer(
         process_->GetID(),
         routing_id_);
   } else {
     // TODO(piman): This is a O(N) lookup, where we could forward the
     // information from the RenderWidgetHelper. The problem is that doing so
     // currently leaks outside of content all the way to chrome classes, and
@@ skipping 97 matching lines @@
     IPC_MESSAGE_HANDLER(ViewHostMsg_RenderViewGone, OnMsgRenderViewGone)
     IPC_MESSAGE_HANDLER(ViewHostMsg_Close, OnMsgClose)
     IPC_MESSAGE_HANDLER(ViewHostMsg_RequestMove, OnMsgRequestMove)
     IPC_MESSAGE_HANDLER(ViewHostMsg_SetTooltipText, OnMsgSetTooltipText)
     IPC_MESSAGE_HANDLER(ViewHostMsg_PaintAtSize_ACK, OnMsgPaintAtSizeAck)
     IPC_MESSAGE_HANDLER(ViewHostMsg_UpdateRect, OnMsgUpdateRect)
     IPC_MESSAGE_HANDLER(ViewHostMsg_UpdateIsDelayed, OnMsgUpdateIsDelayed)
     IPC_MESSAGE_HANDLER(ViewHostMsg_HandleInputEvent_ACK, OnMsgInputEventAck)
     IPC_MESSAGE_HANDLER(ViewHostMsg_Focus, OnMsgFocus)
     IPC_MESSAGE_HANDLER(ViewHostMsg_Blur, OnMsgBlur)
+    IPC_MESSAGE_HANDLER(ViewHostMsg_DidChangeNumTouchEvents,
+                        OnMsgDidChangeNumTouchEvents)
     IPC_MESSAGE_HANDLER(ViewHostMsg_SetCursor, OnMsgSetCursor)
     IPC_MESSAGE_HANDLER(ViewHostMsg_TextInputStateChanged,
                         OnMsgTextInputStateChanged)
     IPC_MESSAGE_HANDLER(ViewHostMsg_ImeCompositionRangeChanged,
                         OnMsgImeCompositionRangeChanged)
     IPC_MESSAGE_HANDLER(ViewHostMsg_ImeCancelComposition,
                         OnMsgImeCancelComposition)
     IPC_MESSAGE_HANDLER(ViewHostMsg_DidActivateAcceleratedCompositing,
                         OnMsgDidActivateAcceleratedCompositing)
     IPC_MESSAGE_HANDLER(ViewHostMsg_LockMouse, OnMsgLockMouse)
@@ skipping 967 matching lines @@
   content::RecordAction(UserMetricsAction("BadMessageTerminate_RWH4"));
   process()->ReceivedBadMessage();
 }
 
 void RenderWidgetHost::OnMsgBlur() {
   // Only RenderViewHost can deal with that message.
   content::RecordAction(UserMetricsAction("BadMessageTerminate_RWH5"));
   process()->ReceivedBadMessage();
 }
 
+void RenderWidgetHost::OnMsgDidChangeNumTouchEvents(int count) {
+  has_touch_handler_ = count > 0;
+}
+
 void RenderWidgetHost::OnMsgSetCursor(const WebCursor& cursor) {
   if (!view_) {
     return;
   }
   view_->UpdateCursor(cursor);
 }
 
 void RenderWidgetHost::OnMsgTextInputStateChanged(
     ui::TextInputType type,
     bool can_compose_inline) {
@@ skipping 317 matching lines @@
     ui_shim->Send(new AcceleratedSurfaceMsg_BuffersSwappedACK(route_id));
 }
 
 // static
 void RenderWidgetHost::AcknowledgePostSubBuffer(int32 route_id,
                                                 int gpu_host_id) {
   GpuProcessHostUIShim* ui_shim = GpuProcessHostUIShim::FromID(gpu_host_id);
   if (ui_shim)
     ui_shim->Send(new AcceleratedSurfaceMsg_PostSubBufferACK(route_id));
 }