PPAPI: Remove out-dated or unnecessary TODOs from public files.

ppapi/api/ppb_graphics_2d.idl

Index: ppapi/api/ppb_graphics_2d.idl
diff --git a/ppapi/api/ppb_graphics_2d.idl b/ppapi/api/ppb_graphics_2d.idl
index 0e0649e2aad498d54131a3b96052d2cf8c441e28..938f428a9c1b0eab0af669198552fa921fb545b4 100644
--- a/ppapi/api/ppb_graphics_2d.idl
+++ b/ppapi/api/ppb_graphics_2d.idl
@@ -239,13 +239,6 @@ interface PPB_Graphics2D {
    * not issued its callback yet.  In the failure case, nothing will be updated
    * and no callback will be scheduled.
    */
-
-  /* TODO(darin): We should ensure that the completion callback always runs, so
-   * that it is easier for consumers to manage memory referenced by a callback.

[dmichael (off chromium), 2012/03/19 17:41:52]

polina's work for "required" callbacks fixed this a while ago (though developers
can still use "optional" callbacks if they want; it's just not the default).

-   *
-   * TODO(): Add back in the synchronous mode description once we have support
-   * for it.

[dmichael (off chromium), 2012/03/19 17:41:52]

That's just part of planned work.

-   */
   int32_t Flush(
       [in] PP_Resource graphics_2d,
       [in] PP_CompletionCallback callback);