Fix redraw of OSR PDF viewer (issue #2507)

patch/patch.cfg

@@ -385,5 +385,10 @@ patches = [
     # Fix VR target dependencies.
     # https://bugs.chromium.org/p/chromium/issues/detail?id=873170
     'name': 'vr_build_873170',
+  },
+  {
+    # Fix redraw of OSR PDF viewer.
+    # https://bitbucket.org/chromiumembedded/cef/issues/2507
+    'name': 'browser_child_frame_2507',
   }
 ]

patch/patches/browser_child_frame_2507.patch

@@ -0,0 +1,20 @@
+diff --git content/browser/renderer_host/render_widget_host_view_child_frame.cc content/browser/renderer_host/render_widget_host_view_child_frame.cc
+index e2dc4f9d8933..84bd61956e42 100644
+--- content/browser/renderer_host/render_widget_host_view_child_frame.cc
++++ content/browser/renderer_host/render_widget_host_view_child_frame.cc
+@@ -630,6 +630,7 @@ void RenderWidgetHostViewChildFrame::SubmitCompositorFrame(
+                "RenderWidgetHostViewChildFrame::OnSwapCompositorFrame");
+   support_->SubmitCompositorFrame(local_surface_id, std::move(frame),
+                                   std::move(hit_test_region_list));
++  ProcessFrameSwappedCallbacks();
+ }
+ 
+ void RenderWidgetHostViewChildFrame::OnDidNotProduceFrame(
+@@ -913,7 +914,6 @@ void RenderWidgetHostViewChildFrame::OnFirstSurfaceActivation(
+   last_activated_surface_info_ = surface_info;
+   has_frame_ = true;
+   FirstSurfaceActivation(surface_info);
+-  ProcessFrameSwappedCallbacks();
+ }
+ 
+ void RenderWidgetHostViewChildFrame::OnFrameTokenChanged(uint32_t frame_token) {