Additional update on Pepper IME API and boilerplate thunk/proxy implementation.

ppapi/proxy/ppapi_messages.h

Index: ppapi/proxy/ppapi_messages.h
diff --git a/ppapi/proxy/ppapi_messages.h b/ppapi/proxy/ppapi_messages.h
index cd54b60cf40dfe6d30db4f402431477f4d9e5153..1bae6cb8f27747908dbe2b7069f76a45ac276fe4 100644
--- a/ppapi/proxy/ppapi_messages.h
+++ b/ppapi/proxy/ppapi_messages.h
@@ -19,6 +19,7 @@
 #include "ipc/ipc_message_utils.h"
 #include "ipc/ipc_platform_file.h"
 #include "ppapi/c/dev/pp_video_capture_dev.h"
+#include "ppapi/c/dev/ppb_text_input_dev.h"
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_file_info.h"
 #include "ppapi/c/pp_instance.h"
@@ -44,6 +45,7 @@
 
 IPC_ENUM_TRAITS(PP_InputEvent_Type)
 IPC_ENUM_TRAITS(PP_InputEvent_MouseButton)
+IPC_ENUM_TRAITS(PP_TextInput_Type)
 IPC_ENUM_TRAITS(PP_VideoDecoder_Profile)
 IPC_ENUM_TRAITS(PP_VideoDecodeError_Dev)
 
@@ -113,6 +115,10 @@ IPC_STRUCT_TRAITS_BEGIN(ppapi::InputEventData)
   IPC_STRUCT_TRAITS_MEMBER(wheel_scroll_by_page)
   IPC_STRUCT_TRAITS_MEMBER(key_code)
   IPC_STRUCT_TRAITS_MEMBER(character_text)
+  IPC_STRUCT_TRAITS_MEMBER(composition_segment_offsets)
+  IPC_STRUCT_TRAITS_MEMBER(composition_target_segment)
+  IPC_STRUCT_TRAITS_MEMBER(composition_selection_start)
+  IPC_STRUCT_TRAITS_MEMBER(composition_selection_end)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_TRAITS_BEGIN(ppapi::PPB_URLRequestInfo_Data)
@@ -878,6 +884,19 @@ IPC_SYNC_MESSAGE_ROUTED1_1(PpapiHostMsg_PPBTesting_GetLiveObjectsForInstance,
                            PP_Instance /* instance */,
                            uint32 /* result */)
 
+// PPB_TextInput.
+IPC_MESSAGE_ROUTED2(PpapiHostMsg_PPBTextInput_SetTextInputType,
+                    PP_Instance /* instance */,
+                    PP_TextInput_Type /* type */)
+IPC_MESSAGE_ROUTED3(PpapiHostMsg_PPBTextInput_UpdateCaretPosition,
+                    PP_Instance /* instance */,
+                    PP_Rect /* caret */,
+                    PP_Rect /* bounding_box */)
+IPC_MESSAGE_ROUTED1(PpapiHostMsg_PPBTextInput_ConfirmCompositionText,
+                    PP_Instance /* instance */)

[James Su, 2011/09/27 04:23:59]

I'm now wondering if ConfirmCompositionText is feasible or not. AFAIK, only
Windows (IMM32) supports such operation, neither Mac nor Linux supports it.
On Windows IMM32, when an application sends such a request to the input method,
the input method should handle it and send back the result text to the
application synchronously.
Because an application usually sends this request before doing some operation
against the text content, so the content needs to be finalized before the
operation. If it happens asynchronously, then it'll be much complex for the
application to support it.

So in order to support it in pepper plugins, it should be a sync call from the
plugin process all the way up to the browser process, and a message containing
the result text must be sent back before the ACK message. It's apparently not
good for chrome's architecture.

Another solution is to fake a sync call by asking the browser to cancel the
composition asynchronously while confirming the current composition text as the
result text synchronously inside the plugin's process. So that we can avoid sync
RPC call completely. But then, I'd rather prefer to just remove this message and
let the plugin confirm the current composition text by itself and send an async
CancelCompositionText message explicitly.

[brettw, 2011/09/27 04:28:42]

If we can remove some complexity by not supporting this function, and still have
a good product, then let's do it. I don't really know how important this is to
the user experience. We can always add stuff later if we determine that it's
important.

[James Su, 2011/09/27 05:06:39]

I think this message is not that important. Chrome does not support such feature
on all platforms, no user complaint so far.

[kinaba, 2011/09/27 05:18:00]

I see. Let us drop it from the API (I've also discussed with Takayoshi offline
and got agreed). Thanks for the detailed explanation.

I'll upload the change soon.

On 2011/09/27 05:06:39, James Su wrote:

[kinaba, 2011/09/27 05:55:36]

Done.

+IPC_MESSAGE_ROUTED1(PpapiHostMsg_PPBTextInput_CancelCompositionText,
+                    PP_Instance /* instance */)
+
 // PPB_URLLoader.
 IPC_SYNC_MESSAGE_ROUTED1_1(PpapiHostMsg_PPBURLLoader_Create,
                            PP_Instance /* instance */,