Add text offset to OnSurroundingTextChanged

chrome/common/extensions/api/input_ime.json

Index: chrome/common/extensions/api/input_ime.json
diff --git a/chrome/common/extensions/api/input_ime.json b/chrome/common/extensions/api/input_ime.json
index cb41d2934f73c2121dccb8d7d40d1188836eeb5a..56680f5982f55c581120b7421186595c0f8cd4de 100644
--- a/chrome/common/extensions/api/input_ime.json
+++ b/chrome/common/extensions/api/input_ime.json
@@ -701,7 +701,11 @@
               },
               "anchor": {
                 "type": "integer",
-                "description": "The beginning position of the selection. This value indicates caret position if is no selection."
+                "description": "The beginning position of the selection. This value indicates caret position if there is no selection."
+              },
+              "offset": {
+                "type": "integer",
+                "description": "The offset position of the selection. This value indicates the number of characters not included in the surrounding text."

[Shu Chen, 2015/08/12 07:23:15]

Please describe clearly for the difference between offset and focus/anchor:
  focus/anchor is relative to the |text|, while offset is relative to the whole
text of the input field, which include the text isn't included in |text|.

[rsadam, 2015/08/12 21:46:52]

Done.

               }
             }
           }