Improve const correctness.

BUG=none
TEST=none

Change-Id: I310a3b6ba78a2eebdc87ffe9a35df05f707b1277
Reviewed-on: https://chromium-review.googlesource.com/894299Reviewed-by: Kentaro Hara <haraken@chromium.org>
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#533195}

content/renderer/render_view_impl.cc

@@ -1045,7 +1045,11 @@ void RenderViewImpl::RemoveObserver(RenderViewObserver* observer) {
   observers_.RemoveObserver(observer);
 }
 
-blink::WebView* RenderViewImpl::webview() const {
+blink::WebView* RenderViewImpl::webview() {
+  return webview_;
+}
+
+const blink::WebView* RenderViewImpl::webview() const {
   return webview_;
 }
 
@@ -1819,8 +1823,8 @@ bool RenderViewImpl::Send(IPC::Message* message) {
   return RenderWidget::Send(message);
 }
 
-RenderWidget* RenderViewImpl::GetWidget() const {
-  return const_cast<RenderWidget*>(static_cast<const RenderWidget*>(this));
+RenderWidget* RenderViewImpl::GetWidget() {
+  return this;
 }
 
 RenderFrameImpl* RenderViewImpl::GetMainRenderFrame() {

content/renderer/render_view_impl.h

@@ -139,10 +139,11 @@ class CONTENT_EXPORT RenderViewImpl : public RenderWidget,
   static RenderViewImpl* FromRoutingID(int routing_id);
 
   // May return NULL when the view is closing.
-  blink::WebView* webview() const;
+  blink::WebView* webview();
+  const blink::WebView* webview() const;
 
   // Returns the RenderWidget for this RenderView.
-  RenderWidget* GetWidget() const;
+  RenderWidget* GetWidget();
 
   const WebPreferences& webkit_preferences() const {
     return webkit_preferences_;