Revert of Revert of Add support for deleting non preceeding surrounding text in chrome.input.ime.deleteSurroundingText

ui/base/ime/input_method_chromeos.cc

 // Copyright 2014 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.
 
 #include "ui/base/ime/input_method_chromeos.h"
 
 #include <algorithm>
 #include <cstring>
 #include <set>
 #include <vector>
@@ skipping 536 matching lines @@
       client->ClearCompositionText();
       SendFakeProcessKeyEvent(false);
     }
     composition_changed_ = false;
   }
 }
 
 void InputMethodChromeOS::DeleteSurroundingText(int32 offset, uint32 length) {
   if (!composition_.text.empty())
     return;  // do nothing if there is ongoing composition.
-  if (offset < 0 && static_cast<uint32>(-1 * offset) != length)
-    return;  // only preceding text can be deletable.
-  if (GetTextInputClient())
-    GetTextInputClient()->ExtendSelectionAndDelete(length, 0U);
+
+  if (GetTextInputClient()) {
+    uint32 before = offset >= 0 ? 0U : static_cast<uint32>(-1 * offset);
+    GetTextInputClient()->ExtendSelectionAndDelete(before, length - before);
+  }
 }
 
 bool InputMethodChromeOS::ExecuteCharacterComposer(const ui::KeyEvent& event) {
   if (!character_composer_.FilterKeyPress(event))
     return false;
 
   // CharacterComposer consumed the key event.  Update the composition text.
   chromeos::CompositionText preedit;
   preedit.set_text(character_composer_.preedit_string());
   UpdateCompositionText(preedit, preedit.text().size(),
@@ skipping 94 matching lines @@
 bool InputMethodChromeOS::IsNonPasswordInputFieldFocused() {
   TextInputType type = GetTextInputType();
   return (type != TEXT_INPUT_TYPE_NONE) && (type != TEXT_INPUT_TYPE_PASSWORD);
 }
 
 bool InputMethodChromeOS::IsInputFieldFocused() {
   return GetTextInputType() != TEXT_INPUT_TYPE_NONE;
 }
 
 }  // namespace ui