Make backspace not go back while IME is active.

chrome/browser/ime_input.cc

 // Copyright (c) 2006-2008 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 "chrome/browser/ime_input.h"
 
 #include "base/scoped_ptr.h"
 #include "base/string_util.h"
 
 // "imm32.lib" is required by IMM32 APIs used in this file.
@@ skipping 158 matching lines @@
 }
 
 void ImeInput::GetCaret(HIMC imm_context, LPARAM lparam,
                         ImeComposition* composition) {
   // This operation is optional and language-dependent because the caret
   // style is depended on the language, e.g.:
   //   * Korean IMEs: the caret is a blinking block,
   //     (It contains only one hangul character);
   //   * Chinese IMEs: the caret is a blinking line,
   //     (i.e. they do not need to retrieve the target selection);
-  //   * Japanese IMEs: the caret is a selection (or undelined) block,
+  //   * Japanese IMEs: the caret is a selection (or underlined) block,
   //     (which can contain one or more Japanese characters).
   int target_start = -1;
   int target_end = -1;
   switch (PRIMARYLANGID(input_language_id_)) {
   case LANG_KOREAN:
     if (lparam & CS_NOMOVECARET) {
       target_start = 0;
       target_end = 1;
     }
     break;
@@ skipping 138 matching lines @@
     // This update is used for moving an IME window when a renderer process
     // resize/moves the input caret.
     if (caret_rect.x() >= 0 && caret_rect.y() >= 0) {
       caret_rect_.SetRect(caret_rect.x(), caret_rect.y(), caret_rect.width(),
                           caret_rect.height());
       MoveImeWindow(window_handle, imm_context);
     }
     ::ImmReleaseContext(window_handle, imm_context);
   }
 }