[sync] Fix sync integration multiprofile tests

crrev.com/c/2066840 made it impossible to create a Chrome profile
outside of the user data directory. Unfortunately, some sync tests
rely on this to be able to test two profiles syncing to the same
account.

This CL adds a command line flag --allow-profiles-outside-user-dir
that restores previous behaviour. This flag should be only used as a
workaround to fix the sync tests before we have more robust solution.

Bug: 1060366
Change-Id: I864a32d5e5d06b029bab1233b33fbb80d27ea137
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2096769
Commit-Queue: Alex Ilin <alexilin@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#749333}

chrome/browser/profiles/profile_manager.cc

@@ -551,7 +551,9 @@ void ProfileManager::CreateProfileAsync(const base::FilePath& profile_path,
                "profile_path",
                profile_path.AsUTF8Unsafe());
 
-  bool is_allowed_path = IsAllowedProfilePath(profile_path);
+  bool is_allowed_path = IsAllowedProfilePath(profile_path) ||
+                         base::CommandLine::ForCurrentProcess()->HasSwitch(
+                             switches::kAllowProfilesOutsideUserDir);
 
   // Make sure the path is correct and this profile is not pending deletion.
   if (!is_allowed_path || IsProfileDirectoryMarkedForDeletion(profile_path)) {
@@ -1415,7 +1417,9 @@ Profile* ProfileManager::CreateAndInitializeProfile(
     const base::FilePath& profile_dir) {
   TRACE_EVENT0("browser", "ProfileManager::CreateAndInitializeProfile");
 
-  if (!IsAllowedProfilePath(profile_dir)) {
+  if (!IsAllowedProfilePath(profile_dir) &&
+      !base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kAllowProfilesOutsideUserDir)) {
     LOG(ERROR) << "Cannot create profile at path "
                << profile_dir.AsUTF8Unsafe();
     return nullptr;

chrome/browser/sync/test/integration/sync_test.cc

@@ -344,6 +344,12 @@ void SyncTest::AddTestSwitches(base::CommandLine* cl) {
   // should be removed.
   if (!cl->HasSwitch(switches::kSyncEnableGetUpdatesBeforeCommit))
     cl->AppendSwitch(switches::kSyncEnableGetUpdatesBeforeCommit);
+
+  // TODO(crbug.com/1060366): This is a temporary switch to allow having two
+  // profiles syncing the same account. Having a profile outside of the user
+  // directory isn't supported in Chrome.
+  if (!cl->HasSwitch(switches::kAllowProfilesOutsideUserDir))
+    cl->AppendSwitch(switches::kAllowProfilesOutsideUserDir);
 }
 
 void SyncTest::BeforeSetupClient(int index,

chrome/common/chrome_switches.cc

@@ -33,6 +33,13 @@ const char kAllowHttpScreenCapture[] = "allow-http-screen-capture";
 // Don't block outdated plugins.
 const char kAllowOutdatedPlugins[]          = "allow-outdated-plugins";
 
+// Allows profiles to be created outside of the user data dir.
+// TODO(https://crbug.com/1060366): Various places in Chrome assume that all
+// profiles are within the user data dir. Some tests need to violate that
+// assumption. The switch should be removed after this workaround is no longer
+// needed.
+const char kAllowProfilesOutsideUserDir[] = "allow-profiles-outside-user-dir";
+
 // By default, an https page cannot run JavaScript, CSS or plugins from http
 // URLs. This provides an override to get the old insecure behavior.
 const char kAllowRunningInsecureContent[]   = "allow-running-insecure-content";

chrome/common/chrome_switches.h

@@ -32,6 +32,7 @@ namespace switches {
 extern const char kAllowCrossOriginAuthPrompt[];
 extern const char kAllowHttpScreenCapture[];
 extern const char kAllowOutdatedPlugins[];
+extern const char kAllowProfilesOutsideUserDir[];
 extern const char kAllowRunningInsecureContent[];
 extern const char kAllowSilentPush[];
 extern const char kApp[];