Reland "Use EarlGrey wait condition instead of spinning the runloop."

This reverts commit 9b7b1b3a.

Reason for revert: Fixed downstream compilation

Original change's description:
> Revert "Use EarlGrey wait condition instead of spinning the runloop."
> 
> This reverts commit 7a4958d3.
> 
> Reason for revert: Downstream code is using signOutAndClearAccounts
> 
> Original change's description:
> > Use EarlGrey wait condition instead of spinning the runloop.
> > 
> > The sign-in external URL tests were spinning the runloop while waiting
> > for the identities to be removed from the ChromeIdentityService. This
> > was consistently failing with EarlGrey2.
> > 
> > This CL uses an EarlGrey wait condition instead of spinning the runloop
> > while waiting for the identities to be removed.
> > 
> > Bug: 1031986
> > 
> > Change-Id: I0bcf6bda55caa506fe3a4d54ee607efc5c2e4d37
> > Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2039551
> > Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
> > Commit-Queue: Mihai Sardarescu <msarda@chromium.org>
> > Cr-Commit-Position: refs/heads/master@{#738916}
> 
> TBR=msarda@chromium.org,sdefresne@chromium.org
> 
> Change-Id: I87b517b4669f02af19c516997eba465f51eb0c22
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: 1031986
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2041753
> Reviewed-by: Gauthier Ambard <gambard@chromium.org>
> Commit-Queue: Gauthier Ambard <gambard@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#738934}

TBR=msarda@chromium.org,sdefresne@chromium.org,gambard@chromium.org

Change-Id: I5be4d0bad2ac69aade4f9707a55303608bfa3644
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1031986
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2041598Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Commit-Queue: Mihai Sardarescu <msarda@chromium.org>
Cr-Commit-Position: refs/heads/master@{#738940}

ios/chrome/test/app/signin_test_util.h

@@ -21,9 +21,12 @@ void SetUpMockAccountReconcilor();
 // Tears down the mock AccountReconcilor if it was previously set up.
 void TearDownMockAccountReconcilor();
 
-// Signs the user out and clears the known accounts entirely. Returns whether
-// the accounts were correctly removed from the keychain.
-bool SignOutAndClearAccounts();
+// Signs the user out and starts clearing all identities from the
+// ChromeIdentityService.
+void SignOutAndClearIdentities();
+
+// Returns true when there are no identities in the ChromeIdentityService.
+bool HasIdentities();
 
 // Resets mock authentication.
 void ResetMockAuthentication();

ios/chrome/test/app/signin_test_util.mm

@@ -29,39 +29,23 @@ namespace chrome_test_util {
 
 namespace {
 
-// Forgets all identities from the ChromeIdentity services. Returns true if all
-// identities were successfully forgotten.
-bool ForgetAllIdentities() {
+// Starts forgetting all identities from the ChromeIdentity services.
+//
+// Note: Forgetting an identity is a asynchronous operation. This function does
+// not wait for the forget identity operation to finish.
+void StartForgetAllIdentities() {
   ios::ChromeIdentityService* identity_service =
       ios::GetChromeBrowserProvider()->GetChromeIdentityService();
-
-  if (!identity_service->HasIdentities())
-    return YES;
-
   NSArray* identities_to_remove =
       [NSArray arrayWithArray:identity_service->GetAllIdentities()];
-  NSMutableArray* identities_left =
-      [NSMutableArray arrayWithArray:identities_to_remove];
-
   for (ChromeIdentity* identity in identities_to_remove) {
     identity_service->ForgetIdentity(identity, ^(NSError* error) {
       if (error) {
         NSLog(@"ForgetIdentity failed: [identity = %@, error = %@]",
               identity.userEmail, [error localizedDescription]);
       }
-      [identities_left removeObject:identity];
     });
   }
-
-  // Wait maximum 10s for all forget identitites to be forgotten.
-  NSDate* deadline = [NSDate dateWithTimeIntervalSinceNow:10.0];
-  while ([identities_left count] &&
-         [[NSDate date] compare:deadline] != NSOrderedDescending) {
-    base::test::ios::SpinRunLoopWithMaxDelay(
-        base::TimeDelta::FromSecondsD(0.01));
-  }
-
-  return !identity_service->HasIdentities();
 }
 
 }  // namespace
@@ -91,7 +75,7 @@ void TearDownMockAccountReconcilor() {
   GaiaAuthFetcherIOS::SetShouldUseGaiaAuthFetcherIOSForTesting(true);
 }
 
-bool SignOutAndClearAccounts() {
+void SignOutAndClearIdentities() {
   // EarlGrey monitors network requests by swizzling internal iOS network
   // objects and expects them to be dealloced before the tear down. It is
   // important to autorelease all objects that make network requests to avoid
@@ -112,15 +96,23 @@ bool SignOutAndClearAccounts() {
     browser_state->GetPrefs()->ClearPref(prefs::kGoogleServicesLastAccountId);
     browser_state->GetPrefs()->ClearPref(prefs::kGoogleServicesLastUsername);
 
-    // |SignOutAndClearAccounts()| is called during shutdown. Commit all pref
+    // |SignOutAndClearIdentities()| is called during shutdown. Commit all pref
     // changes to ensure that clearing the last signed in account is saved on
     // disk in case Chrome crashes during shutdown.
     browser_state->GetPrefs()->CommitPendingWrite();
 
-    return ForgetAllIdentities();
+    // Once the browser was signed out, start clearing all identities from the
+    // ChromeIdentityService.
+    StartForgetAllIdentities();
   }
 }
 
+bool HasIdentities() {
+  ios::ChromeIdentityService* identity_service =
+      ios::GetChromeBrowserProvider()->GetChromeIdentityService();
+  return identity_service->HasIdentities();
+}
+
 void ResetMockAuthentication() {
   ios::FakeChromeIdentityService::GetInstanceFromChromeProvider()
       ->SetFakeMDMError(false);

ios/chrome/test/earl_grey/chrome_earl_grey.h

@@ -315,6 +315,11 @@ id ExecuteJavaScript(NSString* javascript, NSError* __autoreleasing* out_error);
 // Signs the user out, clears the known accounts entirely and checks whether the
 // accounts were correctly removed from the keychain. Induces a GREYAssert if
 // the operation fails.
+- (void)signOutAndClearIdentities;
+
+// Same as signOutAndClearIdentities.
+//
+// DEPRECATED in favor of signOutAndClearIdentities
 - (void)signOutAndClearAccounts;
 
 #pragma mark - Sync Utilities (EG2)

ios/chrome/test/earl_grey/chrome_earl_grey.mm

@@ -32,6 +32,7 @@
 #import "ios/web/public/web_state.h"                             // nogncheck
 #endif
 
+using base::test::ios::kWaitForActionTimeout;
 using base::test::ios::kWaitForJSCompletionTimeout;
 using base::test::ios::kWaitForPageLoadTimeout;
 using base::test::ios::kWaitForUIElementTimeout;
@@ -735,9 +736,21 @@ GREY_STUB_CLASS_IN_APP_MAIN_QUEUE(ChromeEarlGreyAppInterface)
 
 #pragma mark - SignIn Utilities (EG2)
 
+- (void)signOutAndClearIdentities {
+  [ChromeEarlGreyAppInterface signOutAndClearIdentities];
+
+  GREYCondition* allIdentitiesCleared = [GREYCondition
+      conditionWithName:@"All Chrome identities were cleared"
+                  block:^{
+                    return ![ChromeEarlGreyAppInterface hasIdentities];
+                  }];
+  bool success = [allIdentitiesCleared waitWithTimeout:kWaitForActionTimeout];
+  EG_TEST_HELPER_ASSERT_TRUE(success,
+                             @"Failed waiting for identities to be cleared");
+}
+
 - (void)signOutAndClearAccounts {
-  EG_TEST_HELPER_ASSERT_NO_ERROR(
-      [ChromeEarlGreyAppInterface signOutAndClearAccounts]);
+  [self signOutAndClearIdentities];
 }
 
 #pragma mark - Bookmarks Utilities (EG2)

ios/chrome/test/earl_grey/chrome_earl_grey_app_interface.h

@@ -196,10 +196,15 @@
 // Sets value for content setting.
 + (void)setContentSettings:(ContentSetting)setting;
 
-// Signs the user out, clears the known accounts entirely and checks whether
-// the accounts were correctly removed from the keychain. Returns nil on
-// success, or else an NSError indicating why the operation failed.
-+ (NSError*)signOutAndClearAccounts;
+// Signs the user out from Chrome and then starts clearing the identities.
+//
+// Note: This method does not wait for identities to be cleared from the
+// keychain. To wait for this operation to finish, please use an GREYCondition
+// and wait for +hasIdentities to return NO.
++ (void)signOutAndClearIdentities;
+
+// Returns YES if there is at at least identity in the ChromeIdentityService.
++ (BOOL)hasIdentities;
 
 // Returns the current WebState's VisibleURL.
 + (NSString*)webStateVisibleURL;

ios/chrome/test/earl_grey/chrome_earl_grey_app_interface.mm

@@ -364,13 +364,12 @@ using chrome_test_util::BrowserCommandDispatcherForMainBVC;
   chrome_test_util::SetContentSettingsBlockPopups(setting);
 }
 
-+ (NSError*)signOutAndClearAccounts {
-  bool success = chrome_test_util::SignOutAndClearAccounts();
-  if (!success) {
-    return testing::NSErrorWithLocalizedDescription(
-        @"Real accounts couldn't be cleared.");
-  }
-  return nil;
++ (void)signOutAndClearIdentities {
+  chrome_test_util::SignOutAndClearIdentities();
+}
+
++ (BOOL)hasIdentities {
+  return chrome_test_util::HasIdentities();
 }
 
 + (NSString*)webStateVisibleURL {

ios/chrome/test/earl_grey/chrome_test_case.mm

@@ -234,7 +234,7 @@ GREY_STUB_CLASS_IN_APP_MAIN_QUEUE(ChromeTestCaseAppInterface)
   ResetAuthentication();
 
   // Reset any remaining sign-in state from previous tests.
-  [ChromeEarlGrey signOutAndClearAccounts];
+  [ChromeEarlGrey signOutAndClearIdentities];
   [ChromeEarlGrey openNewTab];
   _executedTestMethodSetUp = YES;
 }
@@ -250,7 +250,7 @@ GREY_STUB_CLASS_IN_APP_MAIN_QUEUE(ChromeTestCaseAppInterface)
   }
 
   // Clear any remaining test accounts and signed in users.
-  [ChromeEarlGrey signOutAndClearAccounts];
+  [ChromeEarlGrey signOutAndClearIdentities];
 
   // Re-start anything that was disabled this test, so it is running when the
   // next test starts.
@@ -327,7 +327,7 @@ GREY_STUB_CLASS_IN_APP_MAIN_QUEUE(ChromeTestCaseAppInterface)
 + (void)disableMockAuthentication {
   // Make sure local data is cleared, before disabling mock authentication,
   // where data may be sent to real servers.
-  [ChromeEarlGrey signOutAndClearAccounts];
+  [ChromeEarlGrey signOutAndClearIdentities];
   [ChromeEarlGrey tearDownFakeSyncServer];
   TearDownMockAuthentication();
 }
@@ -458,7 +458,7 @@ GREY_STUB_CLASS_IN_APP_MAIN_QUEUE(ChromeTestCaseAppInterface)
       ResetAuthentication();
 
       // Reset any remaining sign-in state from previous tests.
-      [ChromeEarlGrey signOutAndClearAccounts];
+      [ChromeEarlGrey signOutAndClearIdentities];
       [ChromeEarlGrey openNewTab];
     }
   }