Split ppapi::PluginList from PepperPluginRegistry so that DRT could load pepper plugins.

content/browser/ppapi_broker_process_host.h

Index: content/browser/ppapi_broker_process_host.h
===================================================================
--- content/browser/ppapi_broker_process_host.h	(revision 101488)
+++ content/browser/ppapi_broker_process_host.h	(working copy)
@@ -12,7 +12,11 @@
 #include "base/file_path.h"
 #include "content/browser/browser_child_process_host.h"
 
-struct PepperPluginInfo;
+namespace webkit {
+namespace ppapi {
+struct PluginInfo;
+}
+}
 
 // TODO(ddorwin): Consider merging this with PpapiPluginProcessHost after
 // finishing broker implementation.
@@ -38,7 +42,7 @@
 
   // Actually launches the process with the given plugin info. Returns true
   // on success (the process was spawned).
-  bool Init(const PepperPluginInfo& info);
+  bool Init(const webkit::ppapi::PluginInfo& info);
 
   // Opens a new channel to the plugin. The client will be notified when the
   // channel is ready or if there's an error.