[android_webview] Hardcode the default text encoding to UTF-8.

content/public/renderer/content_renderer_client.h

Index: content/public/renderer/content_renderer_client.h
diff --git a/content/public/renderer/content_renderer_client.h b/content/public/renderer/content_renderer_client.h
index 698e643cb6c6e374f8f5b819dd69d82c2fcf546f..9de7a084bd50c5785570aa0cde7f7aa5ccb41859 100644
--- a/content/public/renderer/content_renderer_client.h
+++ b/content/public/renderer/content_renderer_client.h
@@ -84,9 +84,6 @@ class CONTENT_EXPORT ContentRendererClient {
   // none.
   virtual SkBitmap* GetSadWebViewBitmap();
 
-  // Returns the default text encoding.
-  virtual std::string GetDefaultEncoding();
-
   // Allows the embedder to override creating a plugin. If it returns true, then
   // |plugin| will contain the created plugin, although it could be NULL. If it
   // returns false, the content layer will create the plugin.