Remove grow box rect support, browser part.

blimp/engine/feature/engine_render_widget_feature_unittest.cc

Index: blimp/engine/feature/engine_render_widget_feature_unittest.cc
diff --git a/blimp/engine/feature/engine_render_widget_feature_unittest.cc b/blimp/engine/feature/engine_render_widget_feature_unittest.cc
index 63fd04df4cb3c60a1c8b31cafba8d79320ce38da..4c8ae6d853909791aa7acfe6b1e4def0c4c9e021 100644
--- a/blimp/engine/feature/engine_render_widget_feature_unittest.cc
+++ b/blimp/engine/feature/engine_render_widget_feature_unittest.cc
@@ -85,7 +85,6 @@ class MockRenderWidgetHost
   int GetRoutingID() const override { return 0; }
   content::RenderWidgetHostView* GetView() const override { return nullptr; }
   bool IsLoading() const override { return false; }
-  void ResizeRectChanged(const gfx::Rect& new_rect) override {}
   void RestartHangMonitorTimeout() override {}
   void DisableHangMonitorForTesting() override {}
   void SetIgnoreInputEvents(bool ignore_input_events) override {}