Revamp the MigrateBrowserPrefs and MigrateUserPrefs code.

chrome/common/pref_names.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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 
 #include <stddef.h>
@@ skipping 147 matching lines @@
 extern const char kDnsPrefetchingHostReferralList[];
 extern const char kDisableSpdy[];
 extern const char kHttpServerProperties[];
 extern const char kSpdyServers[];
 extern const char kAlternateProtocolServers[];
 extern const char kDisabledSchemes[];
 #if defined(OS_ANDROID) || defined(OS_IOS)
 extern const char kLastPolicyCheckTime[];
 #endif
 extern const char kInstantUIZeroSuggestUrlPrefix[];
-extern const char kMultipleProfilePrefMigration[];
+extern const char kMultipleProfilePrefMigration[]; // OBSOLETE

[rkaplow, 2015/02/20 21:58:08]

some are marked OBSOLETE. Should I be removing this at this point or just mark
as OBSOLETE?

[gab, 2015/02/23 16:09:37]

The other ones FWICT are declared globally but only used locally for cleanup.

I'd prefer that the ones only needed in browser_prefsl.cc be removed from this
global declaration file and moved to a local file scope declaration in
browser_prefs.cc so that despite still needing them for a while, we keep the
cleanup code as local as possible.

(consider doing this for the 3 existing OBSOLETE prefs as part of this CL as
well)

[rkaplow, 2015/02/23 23:27:52]

already having a bit of trouble keeping track of everything so will not do that
as part of this CL. Added TODO

[gab, 2015/02/24 20:55:19]

Ok NP, though I think kCookieBehavior is the only remaining such OBSOLETE pref
after you removed 2/3 of them in this CL (and it's not referred to by any code,
so it looks like a 2-line strip with no side-effects which may just be easier to
do in this CL)... I rarely advocate for more in the same CL (in fact this CL
could probably be split up but it's not that hard to follow as-is so I didn't
suggest doing so), but in this case feels simple enough to include in this CL.

[rkaplow, 2015/02/24 22:41:11]

You're correct. Done

 extern const char kNetworkPredictionEnabled[];
 extern const char kNetworkPredictionOptions[];
 extern const char kDefaultAppsInstallState[];
 extern const char kHideWebStoreIcon[];
 #if defined(OS_CHROMEOS)
 extern const char kTapToClickEnabled[];
 extern const char kTapDraggingEnabled[];
 extern const char kEnableTouchpadThreeFingerClick[];
 extern const char kNaturalScroll[];
 extern const char kPrimaryMouseButtonRight[];
@@ skipping 305 matching lines @@
 extern const char kStabilityPluginInstances[];
 extern const char kStabilityPluginCrashes[];
 extern const char kStabilityPluginLoadingErrors[];
 
 extern const char kUninstallMetricsPageLoadCount[];
 extern const char kUninstallLastLaunchTimeSec[];
 extern const char kUninstallLastObservedRunTimeSec[];
 
 extern const char kBrowserSuppressDefaultBrowserPrompt[];
 
-extern const char kBrowserWindowPlacement[];
 extern const char kBrowserWindowPlacementPopup[];
 extern const char kTaskManagerWindowPlacement[];
 extern const char kAppWindowPlacement[];
 
 extern const char kDownloadDefaultDirectory[];
 extern const char kDownloadExtensionsToOpen[];
 extern const char kDownloadDirUpgraded[];
 #if defined(OS_WIN) || defined(OS_LINUX) || \
     (defined(OS_MACOSX) && !defined(OS_IOS))
 extern const char kOpenPdfDownloadInSystemReader[];
@@ skipping 317 matching lines @@
 
 extern const char kRegisteredSupervisedUserWhitelists[];
 
 #if defined(ENABLE_EXTENSIONS)
 extern const char kAnimationPolicy[];
 #endif
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_