Add Apps.AppListSearchQueryLength UMA histogram.

ui/app_list/app_list_constants.cc

 // Copyright (c) 2012 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/app_list/app_list_constants.h"
 
 namespace app_list {
 
 const SkColor kContentsBackgroundColor = SkColorSetRGB(0xF2, 0xF2, 0xF2);
 const SkColor kSearchBoxBackground = SK_ColorWHITE;
@@ skipping 111 matching lines @@
 const ui::ResourceBundle::FontStyle kItemTextFontStyle =
     ui::ResourceBundle::SmallFont;
 
 // The UMA histogram that logs which page gets opened by the user.
 const char kPageOpenedHistogram[] = "Apps.AppListPageOpened";
 
 // The UMA histogram that logs the type of search result opened.
 const char kSearchResultOpenDisplayTypeHistogram[] =
     "Apps.AppListSearchResultOpenDisplayType";
 
+// The UMA histogram that logs how long the search query was when a result was
+// opened.
+const char kSearchQueryLength[] = "Apps.AppListSearchQueryLength";
+
 #if defined(OS_LINUX)
 #if defined(GOOGLE_CHROME_BUILD)
 const char kAppListWMClass[] = "chrome_app_list";
 #else  // CHROMIUM_BUILD
 const char kAppListWMClass[] = "chromium_app_list";
 #endif
 #endif
 
 gfx::ShadowValue GetShadowForZHeight(int z_height) {
   if (z_height <= 0)
     return gfx::ShadowValue();
 
   switch (z_height) {
     case 1:
       return gfx::ShadowValue(gfx::Vector2d(0, 1), 2,
                               SkColorSetARGB(0x4C, 0, 0, 0));
     case 2:
       return gfx::ShadowValue(gfx::Vector2d(0, 2), 4,
                               SkColorSetARGB(0x33, 0, 0, 0));
     default:
       return gfx::ShadowValue(gfx::Vector2d(0, 8), 12,
                               SkColorSetARGB(0x3F, 0, 0, 0));
   }
 }
 
 }  // namespace app_list