Remove RWHV::SetBounds() from the public API, and make comments clearer.

content/test/test_render_view_host.h

Index: content/test/test_render_view_host.h
diff --git a/content/test/test_render_view_host.h b/content/test/test_render_view_host.h
index 6b140364bc54d239ebe797f2c4868793a98b7aef..e55aa5e64dcf2326ab3c6d2befc871d055714bb6 100644
--- a/content/test/test_render_view_host.h
+++ b/content/test/test_render_view_host.h
@@ -65,7 +65,6 @@ class TestRenderWidgetHostView : public RenderWidgetHostViewBase {
   void InitAsChild(gfx::NativeView parent_view) override {}
   RenderWidgetHost* GetRenderWidgetHost() const override;
   void SetSize(const gfx::Size& size) override {}
-  void SetBounds(const gfx::Rect& rect) override {}
   gfx::Vector2dF GetLastScrollOffset() const override;
   gfx::NativeView GetNativeView() const override;
   gfx::NativeViewAccessible GetNativeViewAccessible() override;