Add mimetypes on the "chrome-resource://" responses....

chrome/browser/dom_ui/new_tab_ui.h

Index: chrome/browser/dom_ui/new_tab_ui.h
===================================================================
--- chrome/browser/dom_ui/new_tab_ui.h	(revision 5286)
+++ chrome/browser/dom_ui/new_tab_ui.h	(working copy)
@@ -36,6 +36,10 @@
   // the path we registered.
   virtual void StartDataRequest(const std::string& path, int request_id);
 
+  virtual std::string GetMimeType(const std::string&) const {
+    return "text/html";
+  }
+
   // Setters and getters for first_view.
   static void set_first_view(bool first_view) { first_view_ = first_view; }
   static bool first_view() { return first_view_; }
@@ -57,6 +61,10 @@
   // the path we registered.
   virtual void StartDataRequest(const std::string& path, int request_id);
 
+  virtual std::string GetMimeType(const std::string&) const {
+    return "text/html";
+  }
+
  private:
   DISALLOW_EVIL_CONSTRUCTORS(IncognitoTabHTMLSource);
 };
@@ -71,6 +79,11 @@
   // the path we registered.
   virtual void StartDataRequest(const std::string& path, int request_id);
 
+  virtual std::string GetMimeType(const std::string&) const {
+    // Rely on image decoder inferring the correct type.
+    return std::string();
+  }
+
   // Called when thumbnail data is available from the history backend.
   void OnThumbnailDataAvailable(
       HistoryService::Handle request_handle,
@@ -97,6 +110,11 @@
   // the path we registered.
   virtual void StartDataRequest(const std::string& path, int request_id);
 
+  virtual std::string GetMimeType(const std::string&) const {
+    // Rely on image decoder inferring the correct type.
+    return std::string();
+  }
+
   // Called when favicon data is available from the history backend.
   void OnFavIconDataAvailable(
       HistoryService::Handle request_handle,