Clean up RenderWidgetHostView(ChildFrame and Guest) compositing code

content/browser/frame_host/render_widget_host_view_child_frame.cc

Index: content/browser/frame_host/render_widget_host_view_child_frame.cc
diff --git a/content/browser/frame_host/render_widget_host_view_child_frame.cc b/content/browser/frame_host/render_widget_host_view_child_frame.cc
index 0c6bc7dfc596be8f20b7b401f2c0f0d4648e4ff0..47ac1cea1cf98380aadbe9cfa4cfdb05d209392e 100644
--- a/content/browser/frame_host/render_widget_host_view_child_frame.cc
+++ b/content/browser/frame_host/render_widget_host_view_child_frame.cc
@@ -18,7 +18,6 @@
 #include "cc/surfaces/surface.h"
 #include "cc/surfaces/surface_factory.h"
 #include "cc/surfaces/surface_manager.h"
-#include "cc/surfaces/surface_sequence.h"
 #include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/browser_plugin/browser_plugin_guest.h"
 #include "content/browser/compositor/surface_utils.h"
@@ -374,35 +373,29 @@ void RenderWidgetHostViewChildFrame::SurfaceDrawn(
   ack_pending_count_--;
 }
 
-void RenderWidgetHostViewChildFrame::OnSwapCompositorFrame(
+bool RenderWidgetHostViewChildFrame::ShouldRecreateSurface(
     uint32_t compositor_frame_sink_id,
-    cc::CompositorFrame frame) {
-  TRACE_EVENT0("content",
-               "RenderWidgetHostViewChildFrame::OnSwapCompositorFrame");
+    const cc::CompositorFrame& frame) {
+  gfx::Size new_frame_size = frame.render_pass_list.back()->output_rect.size();
+  float new_scale_factor = frame.metadata.device_scale_factor;
 
-  last_scroll_offset_ = frame.metadata.root_scroll_offset;
-
-  if (!frame_connector_)
-    return;
-
-  cc::RenderPass* root_pass = frame.render_pass_list.back().get();
-
-  gfx::Size frame_size = root_pass->output_rect.size();
-  float scale_factor = frame.metadata.device_scale_factor;
+  return compositor_frame_sink_id != last_compositor_frame_sink_id_ ||
+         new_frame_size != current_surface_size_ ||
+         new_scale_factor != current_surface_scale_factor_;
+}
 
-  // Check whether we need to recreate the cc::Surface, which means the child
-  // frame renderer has changed its frame sink, or size, or scale factor.
-  if (compositor_frame_sink_id != last_compositor_frame_sink_id_ ||
-      frame_size != current_surface_size_ ||
-      scale_factor != current_surface_scale_factor_) {
+void RenderWidgetHostViewChildFrame::ProcessCompositorFrame(
+    uint32_t compositor_frame_sink_id,
+    cc::CompositorFrame frame) {
+  if (ShouldRecreateSurface(compositor_frame_sink_id, frame)) {
     ClearCompositorSurfaceIfNecessary();
     // If the renderer changed its frame sink, reset the surface factory to
     // avoid returning stale resources.
     if (compositor_frame_sink_id != last_compositor_frame_sink_id_)
       surface_factory_->Reset();
     last_compositor_frame_sink_id_ = compositor_frame_sink_id;
-    current_surface_size_ = frame_size;
-    current_surface_scale_factor_ = scale_factor;
+    current_surface_size_ = frame.render_pass_list.back()->output_rect.size();
+    current_surface_scale_factor_ = frame.metadata.device_scale_factor;
   }
 
   bool allocated_new_local_frame_id = false;
@@ -428,13 +421,29 @@ void RenderWidgetHostViewChildFrame::OnSwapCompositorFrame(
     cc::SurfaceManager* manager = GetSurfaceManager();
     manager->GetSurfaceForId(cc::SurfaceId(frame_sink_id_, local_frame_id_))
         ->AddDestructionDependency(sequence);
-    frame_connector_->SetChildFrameSurface(
-        cc::SurfaceId(frame_sink_id_, local_frame_id_), frame_size,
-        scale_factor, sequence);
+    SendSurfaceInfoToChild(sequence);
   }
   ProcessFrameSwappedCallbacks();
 }
 
+void RenderWidgetHostViewChildFrame::SendSurfaceInfoToChild(
+    const cc::SurfaceSequence& sequence) {
+  frame_connector_->SetChildFrameSurface(
+      cc::SurfaceId(frame_sink_id_, local_frame_id_), current_surface_size_,
+      current_surface_scale_factor_, sequence);
+}
+
+void RenderWidgetHostViewChildFrame::OnSwapCompositorFrame(
+    uint32_t compositor_frame_sink_id,
+    cc::CompositorFrame frame) {
+  TRACE_EVENT0("content",
+               "RenderWidgetHostViewChildFrame::OnSwapCompositorFrame");
+  last_scroll_offset_ = frame.metadata.root_scroll_offset;
+  if (!frame_connector_)
+    return;
+  ProcessCompositorFrame(compositor_frame_sink_id, std::move(frame));
+}
+
 void RenderWidgetHostViewChildFrame::ProcessFrameSwappedCallbacks() {
   // We only use callbacks once, therefore we make a new list for registration
   // before we start, and discard the old list entries when we are done.