Remove RenderViewHost parameter from WebContentsObserver::Did{Start|Stop}Loading.

extensions/browser/guest_view/guest_view_base.cc

Index: extensions/browser/guest_view/guest_view_base.cc
diff --git a/extensions/browser/guest_view/guest_view_base.cc b/extensions/browser/guest_view/guest_view_base.cc
index 3a3c7ffe8ac87f431107bc96ad8dc1c06b4b2652..7edb750265fd0975b32ba8ac2e9ad2e287993035 100644
--- a/extensions/browser/guest_view/guest_view_base.cc
+++ b/extensions/browser/guest_view/guest_view_base.cc
@@ -518,18 +518,20 @@ double GuestViewBase::PhysicalPixelsToLogicalPixels(int physical_pixels) {
   return physical_pixels / zoom_factor;
 }
 
-void GuestViewBase::DidStopLoading(content::RenderViewHost* render_view_host) {
+void GuestViewBase::DidStopLoading() {
+  content::RenderViewHost* rvh = web_contents()->GetRenderViewHost();
+
   if (IsPreferredSizeModeEnabled()) {
-    render_view_host->EnablePreferredSizeMode();
+    rvh->EnablePreferredSizeMode();
   }
   if (!IsDragAndDropEnabled()) {
-    const char script[] = "window.addEventListener('dragstart', function() { "
-                          "  window.event.preventDefault(); "
-                          "});";
-    render_view_host->GetMainFrame()->ExecuteJavaScript(
-        base::ASCIIToUTF16(script));
+    const char script[] =
+        "window.addEventListener('dragstart', function() { "
+        "  window.event.preventDefault(); "
+        "});";
+    rvh->GetMainFrame()->ExecuteJavaScript(base::ASCIIToUTF16(script));
   }
-  DidStopLoading();
+  GuestViewDidStopLoading();
 }
 
 void GuestViewBase::RenderViewReady() {