Add a hang monitor for Pepper plugins

content/common/view_messages.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // IPC messages for page rendering.
 // Multiply-included message file, hence no include guard.
 
 #include "base/process.h"
 #include "base/shared_memory.h"
 #include "content/common/content_export.h"
@@ skipping 1158 matching lines @@
 
 // Instructs the renderer to save the current page to MHTML.
 IPC_MESSAGE_ROUTED2(ViewMsg_SavePageAsMHTML,
                     int /* job_id */,
                     IPC::PlatformFileForTransit /* file handle */)
 
 // Temporary message to diagnose an unexpected condition in TabContents.
 IPC_MESSAGE_CONTROL1(ViewMsg_TempCrashWithData,
                      GURL /* data */)
 
+// Enable or disable inverting of web content pixels, for users who prefer
+// white-on-black.
+IPC_MESSAGE_ROUTED1(ViewMsg_InvertWebContent,
+                    bool /* invert */)
 
+// -----------------------------------------------------------------------------
 // Messages sent from the renderer to the browser.
 
 // Sent by the renderer when it is creating a new window.  The browser creates
 // a tab for it and responds with a ViewMsg_CreatingNew_ACK.  If route_id is
 // MSG_ROUTING_NONE, the view couldn't be created.
 IPC_SYNC_MESSAGE_CONTROL1_3(ViewHostMsg_CreateWindow,
                             ViewHostMsg_CreateWindow_Params,
                             int /* route_id */,
                             int32 /* surface_id */,
                             int64 /* cloned_session_storage_namespace_id */)
@@ skipping 446 matching lines @@
 IPC_MESSAGE_ROUTED1(ViewHostMsg_DidChangeNumTouchEvents,
                     int /* count */)
 
 // A message from HTML-based UI.  When (trusted) Javascript calls
 // send(message, args), this message is sent to the browser.
 IPC_MESSAGE_ROUTED3(ViewHostMsg_WebUISend,
                     GURL /* source_url */,
                     std::string  /* message */,
                     base::ListValue /* args */)
 
-// A renderer sends this to the browser process when it wants to
-// create a ppapi plugin.  The browser will create the plugin process if
-// necessary, and will return a handle to the channel on success.
-// On error an empty string is returned.
-IPC_SYNC_MESSAGE_CONTROL1_2(ViewHostMsg_OpenChannelToPepperPlugin,
+// A renderer sends this to the browser process when it wants to create a ppapi
+// plugin.  The browser will create the plugin process if necessary, and will
+// return a handle to the channel on success.
+//
+// The plugin_child_id is the ChildProcessHost ID assigned in the browser
+// process. This ID is valid only in the context of the browser process and is
+// used to identify the proper process when the renderer notifies it that the
+// plugin is hung.
+//
+// On error an empty string and null handles are returned.
+IPC_SYNC_MESSAGE_CONTROL1_3(ViewHostMsg_OpenChannelToPepperPlugin,
                             FilePath /* path */,
                             base::ProcessHandle /* plugin_process_handle */,
-                            IPC::ChannelHandle /* handle to channel */)
+                            IPC::ChannelHandle /* handle to channel */,
+                            int /* plugin_child_id */)
 
 // A renderer sends this to the browser process when it wants to
 // create a ppapi broker.  The browser will create the broker process
 // if necessary, and will return a handle to the channel on success.
 // On error an empty string is returned.
 // The browser will respond with ViewMsg_PpapiBrokerChannelCreated.
 IPC_MESSAGE_CONTROL3(ViewHostMsg_OpenChannelToPpapiBroker,
                      int /* routing_id */,
                      int /* request_id */,
                      FilePath /* path */)
@@ skipping 322 matching lines @@
 
 // Following message is used to communicate the values received by the
 // callback binding the JS to Cpp.
 // An instance of browser that has an automation host listening to it can
 // have a javascript send a native value (string, number, boolean) to the
 // listener in Cpp. (DomAutomationController)
 IPC_MESSAGE_ROUTED2(ViewHostMsg_DomOperationResponse,
                     std::string  /* json_string */,
                     int  /* automation_id */)
 
-// Enable or disable inverting of web content pixels, for users who prefer
-// white-on-black.
-IPC_MESSAGE_ROUTED1(ViewMsg_InvertWebContent,
-                    bool /* invert */)
+// Sent to the browser when the renderer detects it is blocked on a pepper
+// plugin message for too long. This is also sent when it becomes unhung
+// (according to the value of is_hung). The browser can give the user the
+// option of killing the plugin.
+IPC_MESSAGE_ROUTED3(ViewHostMsg_PepperPluginHung,
+                    int /* plugin_child_id */,
+                    FilePath /* path */,
+                    bool /* is_hung */)