Add UMA for --app-shim-error.

chrome/common/mac/app_mode_common.h

 // 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.
 
 #ifndef CHROME_COMMON_MAC_APP_MODE_COMMON_H_
 #define CHROME_COMMON_MAC_APP_MODE_COMMON_H_
 
 #import <Foundation/Foundation.h>
 
 #include "base/files/file_path.h"
@@ skipping 31 matching lines @@
 extern const char kLaunchedForTest[];
 
 // Indicates to the shim that this Chrome has rebuilt it once already, i.e. if
 // it fails to launch again, don't trigger another rebuild.
 extern const char kLaunchedAfterRebuild[];
 
 // Path to an app shim bundle. Indicates to Chrome that this shim attempted to
 // launch but failed.
 extern const char kAppShimError[];
 
+// The reason for the above app shim error. Should be one of the following.
+extern const char kAppShimErrorDetail[];
+
+// This was a 32 bit shim.
+extern const char kAppShimErrorDetail32Bit[];
+
+// This was a 64 bit shim.
+extern const char kAppShimErrorDetail64Bit[];
+
 // Keys for specifying the file types handled by an app.
 extern NSString* const kCFBundleDocumentTypesKey;
 extern NSString* const kCFBundleTypeExtensionsKey;
 extern NSString* const kCFBundleTypeIconFileKey;
 extern NSString* const kCFBundleTypeNameKey;
 extern NSString* const kCFBundleTypeMIMETypesKey;
 extern NSString* const kCFBundleTypeRoleKey;
 extern NSString* const kBundleTypeRoleViewer;
 
 // The display name of the bundle as shown in Finder and the Dock. For localized
@@ skipping 89 matching lines @@
   base::FilePath profile_dir;
 };
 
 // Check that the socket and its parent directory have the correct permissions
 // and are owned by the user.
 void VerifySocketPermissions(const base::FilePath& socket_path);
 
 }  // namespace app_mode
 
 #endif  // CHROME_COMMON_MAC_APP_MODE_COMMON_H_