sync compositor: Async scroll offset IPC

content/browser/android/synchronous_compositor_host.cc

 // Copyright 2015 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/android/synchronous_compositor_host.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
@@ skipping 59 matching lines @@
     : rwhva_(rwhva),
       client_(client),
       ui_task_runner_(
           BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI)),
       routing_id_(rwhva_->GetRenderWidgetHost()->GetRoutingID()),
       sender_(rwhva_->GetRenderWidgetHost()),
       async_input_(async_input),
       use_in_process_zero_copy_software_draw_(use_in_proc_software_draw),
       is_active_(false),
       bytes_limit_(0u),
-      root_scroll_offset_updated_by_browser_(false),
       renderer_param_version_(0u),
       need_animate_scroll_(false),
       need_invalidate_count_(0u),
       need_begin_frame_(false),
       did_activate_pending_tree_count_(0u),
       weak_ptr_factory_(this) {
   client_->DidInitializeCompositor(this);
 }
 
 SynchronousCompositorHost::~SynchronousCompositorHost() {
@@ skipping 231 matching lines @@
   if (sender_->Send(
           new SyncCompositorMsg_SetMemoryPolicy(routing_id_, bytes_limit))) {
     bytes_limit_ = bytes_limit;
   }
 }
 
 void SynchronousCompositorHost::DidChangeRootLayerScrollOffset(
     const gfx::ScrollOffset& root_offset) {
   if (root_scroll_offset_ == root_offset)
     return;
-  root_scroll_offset_updated_by_browser_ = true;
   root_scroll_offset_ = root_offset;
-  SendAsyncCompositorStateIfNeeded();
+  sender_->Send(
+      new SyncCompositorMsg_SetScroll(routing_id_, root_scroll_offset_));
 }
 
 void SynchronousCompositorHost::SendAsyncCompositorStateIfNeeded() {
   if (weak_ptr_factory_.HasWeakPtrs())
     return;
 
   ui_task_runner_->PostTask(
       FROM_HERE, base::Bind(&SynchronousCompositorHost::UpdateStateTask,
                             weak_ptr_factory_.GetWeakPtr()));
 }
@@ skipping 89 matching lines @@
 void SynchronousCompositorHost::OnOverScroll(
     const SyncCompositorCommonRendererParams& params,
     const DidOverscrollParams& over_scroll_params) {
   ProcessCommonParams(params);
   DidOverscroll(over_scroll_params);
 }
 
 void SynchronousCompositorHost::PopulateCommonParams(
     SyncCompositorCommonBrowserParams* params) {
   DCHECK(params);
-  if (root_scroll_offset_updated_by_browser_) {
-    params->root_scroll_offset = root_scroll_offset_;
-    params->update_root_scroll_offset = root_scroll_offset_updated_by_browser_;
-    root_scroll_offset_updated_by_browser_ = false;
-  }
   params->begin_frame_source_paused = !is_active_;
 
   weak_ptr_factory_.InvalidateWeakPtrs();
 }
 
 void SynchronousCompositorHost::ProcessCommonParams(
     const SyncCompositorCommonRendererParams& params) {
   // Ignore if |renderer_param_version_| is newer than |params.version|. This
   // comparison takes into account when the unsigned int wraps.
   if ((renderer_param_version_ - params.version) < 0x80000000) {
@@ skipping 28 matching lines @@
         params.scrollable_size, params.page_scale_factor,
         params.min_page_scale_factor, params.max_page_scale_factor);
   }
 }
 
 void SynchronousCompositorHost::UpdateNeedsBeginFrames() {
   rwhva_->OnSetNeedsBeginFrames(is_active_ && need_begin_frame_);
 }
 
 }  // namespace content