Replace string16 with base::string16 in src/webkit

webkit/plugins/ppapi/plugin_delegate.h

Index: webkit/plugins/ppapi/plugin_delegate.h
diff --git a/webkit/plugins/ppapi/plugin_delegate.h b/webkit/plugins/ppapi/plugin_delegate.h
index 1c861e8abbd877f667e54fd1276945b628d82588..3a8a7248b175d79d316753f9eda714e7410a255b 100644
--- a/webkit/plugins/ppapi/plugin_delegate.h
+++ b/webkit/plugins/ppapi/plugin_delegate.h
@@ -362,11 +362,11 @@ class PluginDelegate {
       webkit::ppapi::PluginInstance* instance) = 0;
   // Requests simulating IME events for testing purpose.
   virtual void SimulateImeSetComposition(
-      const string16& text,
+      const base::string16& text,
       const std::vector<WebKit::WebCompositionUnderline>& underlines,
       int selection_start,
       int selection_end) = 0;
-  virtual void SimulateImeConfirmComposition(const string16& text) = 0;
+  virtual void SimulateImeConfirmComposition(const base::string16& text) = 0;
 
   // Notification that the given plugin has crashed. When a plugin crashes, all
   // instances associated with that plugin will notify that they've crashed via