Introduce default implementation for TabContentsDelegate::ViewSourceForTab.

chrome/browser/tab_contents/tab_contents_delegate.cc

Index: chrome/browser/tab_contents/tab_contents_delegate.cc
diff --git a/chrome/browser/tab_contents/tab_contents_delegate.cc b/chrome/browser/tab_contents/tab_contents_delegate.cc
index 319407d08aafb8b84407716ab58b0ace64a0099e..3b16cf96e77ae800e5fa69b0a395522635632d46 100644
--- a/chrome/browser/tab_contents/tab_contents_delegate.cc
+++ b/chrome/browser/tab_contents/tab_contents_delegate.cc
@@ -5,6 +5,7 @@
 #include "chrome/browser/tab_contents/tab_contents_delegate.h"
 
 #include "chrome/browser/search_engines/template_url.h"
+#include "chrome/common/url_constants.h"
 #include "gfx/rect.h"
 
 std::string TabContentsDelegate::GetNavigationHeaders(const GURL& url) {
@@ -131,7 +132,18 @@ void TabContentsDelegate::ShowPageInfo(Profile* profile,
                                        bool show_history) {
 }
 
-void TabContentsDelegate::ViewSourceForTab(TabContents* source) {
+void TabContentsDelegate::ViewSourceForTab(TabContents* source,
+                                           const GURL& page_url) {
+  // Fall back implementation based entirely on the view-source scheme.
+  // It suffers from http://crbug.com/523 and that is why browser overrides
+  // it with proper implementation.
+  GURL url = GURL(chrome::kViewSourceScheme + std::string(":") +
+                      page_url.spec());
+  OpenURLFromTab(source,
+                 url,
+                 GURL(),
+                 NEW_FOREGROUND_TAB,
+                 PageTransition::LINK);
 }
 
 bool TabContentsDelegate::PreHandleKeyboardEvent(