Add IPC::Sender and GetRoutingID() to WebContents for convenience and safety.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index d5a09dcbb874a55aa40e394cedb5f2975d3edf94..4d07d2313cd2b37abbcbe9908d97ca9e78dfcc34 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -743,6 +743,13 @@ RenderViewHost* WebContentsImpl::GetRenderViewHost() const {
   return render_manager_.current_host();
 }
 
+int WebContentsImpl::GetRoutingID() const {
+  if (!GetRenderViewHost())
+    return MSG_ROUTING_NONE;
+
+  return GetRenderViewHost()->GetRoutingID();
+}
+
 RenderWidgetHostView* WebContentsImpl::GetRenderWidgetHostView() const {
   return render_manager_.GetRenderWidgetHostView();
 }
@@ -1441,6 +1448,15 @@ WebContents* WebContentsImpl::OpenURL(const OpenURLParams& params) {
   return new_contents;
 }
 
+bool WebContentsImpl::Send(IPC::Message* message) {
+  if (!GetRenderViewHost()) {
+    delete message;
+    return false;
+  }
+
+  return GetRenderViewHost()->Send(message);
+}
+
 bool WebContentsImpl::NavigateToPendingEntry(
     NavigationController::ReloadType reload_type) {
   return NavigateToEntry(
@@ -1551,9 +1567,9 @@ void WebContentsImpl::SetHistoryLengthAndPrune(
     NOTREACHED();
     return;
   }
-  rvh->Send(new ViewMsg_SetHistoryLengthAndPrune(rvh->GetRoutingID(),
-                                                 history_length,
-                                                 minimum_page_id));
+  Send(new ViewMsg_SetHistoryLengthAndPrune(GetRoutingID(),
+                                            history_length,
+                                            minimum_page_id));
 }
 
 void WebContentsImpl::FocusThroughTabTraversal(bool reverse) {
@@ -1638,14 +1654,12 @@ bool WebContentsImpl::WillNotifyDisconnection() const {
 
 void WebContentsImpl::SetOverrideEncoding(const std::string& encoding) {
   SetEncoding(encoding);
-  GetRenderViewHostImpl()->Send(new ViewMsg_SetPageEncoding(
-      GetRenderViewHost()->GetRoutingID(), encoding));
+  Send(new ViewMsg_SetPageEncoding(GetRoutingID(), encoding));
 }
 
 void WebContentsImpl::ResetOverrideEncoding() {
   encoding_.clear();
-  GetRenderViewHostImpl()->Send(new ViewMsg_ResetPageEncodingToDefault(
-      GetRenderViewHost()->GetRoutingID()));
+  Send(new ViewMsg_ResetPageEncodingToDefault(GetRoutingID()));
 }
 
 content::RendererPreferences* WebContentsImpl::GetMutableRendererPrefs() {
@@ -1827,13 +1841,12 @@ bool WebContentsImpl::HasOpener() const {
 
 void WebContentsImpl::DidChooseColorInColorChooser(int color_chooser_id,
                                                    SkColor color) {
-  GetRenderViewHost()->Send(new ViewMsg_DidChooseColorResponse(
-      GetRenderViewHost()->GetRoutingID(), color_chooser_id, color));
+  Send(new ViewMsg_DidChooseColorResponse(
+      GetRoutingID(), color_chooser_id, color));
 }
 
 void WebContentsImpl::DidEndColorChooser(int color_chooser_id) {
-  GetRenderViewHost()->Send(new ViewMsg_DidEndColorChooser(
-      GetRenderViewHost()->GetRoutingID(), color_chooser_id));
+  Send(new ViewMsg_DidEndColorChooser(GetRoutingID(), color_chooser_id));
   if (delegate_)
     delegate_->DidEndColorChooser();
   color_chooser_ = NULL;
@@ -2444,8 +2457,7 @@ void WebContentsImpl::RenderViewCreated(RenderViewHost* render_view_host) {
 
   if (entry->IsViewSourceMode()) {
     // Put the renderer in view source mode.
-    static_cast<RenderViewHostImpl*>(render_view_host)->Send(
-        new ViewMsg_EnableViewSourceMode(render_view_host->GetRoutingID()));
+    Send(new ViewMsg_EnableViewSourceMode(GetRoutingID()));

[jam, 2012/08/15 16:22:02]

I think you need to keep this as is.

render_view_host might not be equal to GetRenderViewHost() in case of pending
RVHs

[Jói, 2012/08/15 19:13:24]

Phew, thanks for catching that!

   }
 
   GetView()->RenderViewCreated(render_view_host);
@@ -2838,8 +2850,7 @@ void WebContentsImpl::RouteMessageEvent(
   // In most cases, we receive this from a swapped out RenderViewHost.
   // It is possible to receive it from one that has just been swapped in,
   // in which case we might as well deliver the message anyway.
-  GetRenderViewHost()->Send(new ViewMsg_PostMessageEvent(
-      GetRenderViewHost()->GetRoutingID(), new_params));
+  Send(new ViewMsg_PostMessageEvent(GetRoutingID(), new_params));
 }
 
 void WebContentsImpl::RunJavaScriptMessage(