Expose CompositorDependencies from PageProperties.

This CL is a refactor with no intended behavior change.

The member was already there. This CL simply exposes it and starts using it,
rather than calling RenderWidget::compositor_deps(), since |render_widget_| may
be nullptr in the future.

Bug: 912193
Change-Id: Ib36ee51473100f2cee8fc685f6817647a1c6fc08
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1829675
Auto-Submit: Erik Chen <erikchen@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#701651}

content/renderer/page_properties.cc

@@ -56,4 +56,8 @@ const ScreenInfo& PageProperties::GetOriginalScreenInfo() const {
              : GetScreenInfo();
 }
 
+CompositorDependencies* PageProperties::GetCompositorDependencies() {
+  return compositor_deps_;
+}
+
 }  // namespace content

content/renderer/page_properties.h

@@ -58,6 +58,8 @@ class CONTENT_EXPORT PageProperties {
   // When emulated, this returns the original (non-emulated) ScreenInfo.
   const ScreenInfo& GetOriginalScreenInfo() const;
 
+  CompositorDependencies* GetCompositorDependencies();
+
  private:
   // Properties of the screen hosting the page.
   ScreenInfo screen_info_;

content/renderer/render_view_impl.cc

@@ -1432,7 +1432,7 @@ WebView* RenderViewImpl::CreateView(
                      base::Unretained(creator_frame), opened_by_user_gesture);
 
   RenderViewImpl* view = RenderViewImpl::Create(
-      render_widget_->compositor_deps(), std::move(view_params),
+      page_properties_.GetCompositorDependencies(), std::move(view_params),
       std::move(show_callback),
       creator->GetTaskRunner(blink::TaskType::kInternalDefault));