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

ppapi/api/dev/ppb_ime_input_event_dev.idl

 /* Copyright (c) 2011 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.
  */
 
 /**
  * This file defines the <code>PPB_IMEInputEvent_Dev</code> interface.
  */
 
 label Chrome {
@@ skipping 28 matching lines @@
    *
    * @param[in] ime_event A <code>PP_Resource</code> corresponding to an IME
    * event.
    *
    * @return The number of segments. For events other than COMPOSITION_UPDATE,
    * returns 0.
    */
   uint32_t GetSegmentNumber([in] PP_Resource ime_event);
 
   /**
-   * GetSegmentAt() returns the start and the end position of the index-th
-   * segment in the composition text. The positions are given by byte-offsets
-   * (not character-offsets) of the string returned by GetText(). The range of
-   * the segment extends from start (inclusive) to end (exclusive). They satisfy
-   * 0 <= start < end <= (byte-length of GetText()). When the event is not
-   * COMPOSITION_UPDATE or index >= GetSegmentNumber(), the function returns
-   * PP_FALSE and nothing else happens.
+   * GetSegmentOffset() returns the position of the index-th segmentation point
+   * in the composition text. The position is given by a byte-offset (not a
+   * character-offset) of the string returned by GetText(). It always satisfies
+   * 0=GetSegmentOffset(0) < ... < GetSegmentOffset(i) < GetSegmentOffset(i+1)
+   * < ... < GetSegmentOffset(GetSegmentNumber())=(byte-length of GetText()).
+   * Note that [GetSegmentOffset(i), GetSegmentOffset(i+1)) represents the range
+   * of the i-th segment, and hence GetSegmentNumber() can be a valid argument
+   * to this function instead of an off-by-1 error.
    *
    * @param[in] ime_event A <code>PP_Resource</code> corresponding to an IME
    * event.
    *
    * @param[in] index An integer indicating a segment.
    *
-   * @param[out] start The start position of the index-th segment.
-   *
-   * @param[out] end The end position of the index-th segment.
-   *
-   * @return PP_TRUE when the start and the end position is successfully
-   * obtained, and PP_FALSE otherwise.
+   * @return The byte-offset of the segmentation point. If the event is not
+   * COMPOSITION_UPDATE or index is out of range, returns 0.
    */
-  PP_Bool GetSegmentAt([in] PP_Resource ime_event,
-                       [in] uint32_t index,
-                       [out] uint32_t start,
-                       [out] uint32_t end);
+  uint32_t GetSegmentOffset([in] PP_Resource ime_event,
+                            [in] uint32_t index);
 
   /**
    * GetTargetSegment() returns the index of the current target segment of
    * composition.
    *
    * @param[in] ime_event A <code>PP_Resource</code> corresponding to an IME
    * event.
    *
    * @return An integer indicating the index of the target segment. When there
    * is no active target segment, or the event is not COMPOSITION_UPDATE,
    * returns -1.
    */
   int32_t GetTargetSegment([in] PP_Resource ime_event);
 
   /**
    * GetSelection() returns the range selected by caret in the composition text.
    *
    * @param[in] ime_event A <code>PP_Resource</code> corresponding to an IME
    * event.
    *
    * @param[out] start The start position of the current selection.
    *
    * @param[out] end The end position of the current selection.
    */
   void GetSelection([in] PP_Resource ime_event,
                     [out] uint32_t start,
                     [out] uint32_t end);
 };