Fix an IME regression for <webview> due to missing IPC message param

content/common/browser_plugin/browser_plugin_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.
 
 // Multiply-included message header, no traditional include guard.
 
 #include <string>
 
 #include "base/process/process.h"
 #include "cc/surfaces/surface.h"
@@ skipping 40 matching lines @@
   IPC_STRUCT_MEMBER(int, selection_start)
   IPC_STRUCT_MEMBER(int, selection_end)
 IPC_STRUCT_END()
 
 // Browser plugin messages
 
 // -----------------------------------------------------------------------------
 // These messages are from the embedder to the browser process.
 // Most messages from the embedder to the browser process are CONTROL because
 // they are routed to the appropriate BrowserPluginGuest based on the
-// browser_plugin_instance_id which is unique per embedder process.
+// |browser_plugin_instance_id| which is unique per embedder process.
+// |browser_plugin_instance_id| is only used by BrowserPluginMessageFilter to
+// find the right BrowserPluginGuest. It should not be needed by the final IPC
+// handler.
 
 // This message is sent from BrowserPlugin to BrowserPluginGuest to issue an
 // edit command.
 IPC_MESSAGE_CONTROL2(BrowserPluginHostMsg_ExecuteEditCommand,
                      int /* browser_plugin_instance_id */,
                      std::string /* command */)
 
 // This message must be sent just before sending a key event.
 IPC_MESSAGE_CONTROL2(BrowserPluginHostMsg_SetEditCommandsForNextKeyEvent,
                      int /* browser_plugin_instance_id */,
@@ skipping 10 matching lines @@
 IPC_MESSAGE_CONTROL5(
     BrowserPluginHostMsg_ImeCommitText,
     int /* browser_plugin_instance_id */,
     base::string16 /* text */,
     std::vector<blink::WebCompositionUnderline> /* underlines */,
     gfx::Range /* replacement_range */,
     int /* relative_cursor_pos */)
 
 // This message is sent from BrowserPlugin to BrowserPluginGuest to notify that
 // inserting the current composition is requested.
-IPC_MESSAGE_CONTROL1(BrowserPluginHostMsg_ImeFinishComposingText,
+IPC_MESSAGE_CONTROL2(BrowserPluginHostMsg_ImeFinishComposingText,
+                     int /* browser_plugin_instance_id */,
                      bool /* keep selection */)
 
 // Deletes the current selection plus the specified number of characters before
 // and after the selection or caret.
 IPC_MESSAGE_CONTROL3(BrowserPluginHostMsg_ExtendSelectionAndDelete,
                      int /* browser_plugin_instance_id */,
                      int /* before */,
                      int /* after */)
 
 // This message is sent to the browser process to indicate that the
@@ skipping 94 matching lines @@
 
 // Forwards a PointerLock Unlock request to the BrowserPlugin.
 IPC_MESSAGE_CONTROL2(BrowserPluginMsg_SetMouseLock,
                      int /* browser_plugin_instance_id */,
                      bool /* enable */)
 
 // Sends text to be displayed in tooltip.
 IPC_MESSAGE_CONTROL2(BrowserPluginMsg_SetTooltipText,
                      int /* browser_plugin_instance_id */,
                      base::string16 /* tooltip_text */)