[ios] Re-enable flaky navigation restore egtests.

Both testRestoreHistory tests were emulating a background/kill/restore
by simply disabling/enabling web usage.  Doing a tabgrid close all /
undo is more similar.

Upon EG2 migration, this method can be removed, and the test can do
a proper background/kill/restore.

Bug: 1011791
Change-Id: I1f3074917747551833ef090e2da598674476de77
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1846072
Commit-Queue: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703475}

ios/chrome/browser/web/navigation_egtest.mm

@@ -559,15 +559,14 @@ std::unique_ptr<net::test_server::HttpResponse> WindowLocationHashHandlers(
 
 // Tests that navigating forward from a WebUI URL works when resuming from
 // session restore. This is a regression test for https://crbug.com/814790.
-// TODO(crbug.com/1011791): Test disabled.
-- (void)DISABLED_testRestoreHistoryToWebUIAndNavigateForward {
+- (void)testRestoreHistoryToWebUIAndNavigateForward {
   GREYAssertTrue(self.testServer->Start(), @"Test server failed to start.");
   const GURL destinationURL = self.testServer->GetURL(kSimpleFileBasedTestURL);
   [ChromeEarlGrey loadURL:GURL("chrome://version")];
   [ChromeEarlGrey loadURL:destinationURL];
   [ChromeEarlGrey goBack];
 
-  [ChromeEarlGrey purgeCachedWebViewPages];
+  [ChromeEarlGrey triggerRestoreViaTabGridRemoveAllUndo];
 
   [ChromeEarlGrey waitForWebStateContainingText:"Revision"];
   [[EarlGrey selectElementWithMatcher:OmniboxText("chrome://version")]
@@ -580,14 +579,13 @@ std::unique_ptr<net::test_server::HttpResponse> WindowLocationHashHandlers(
 
 // Tests that navigating forward from NTP works when resuming from session
 // restore. This is a regression test for https://crbug.com/814790.
-// TODO(crbug.com/1011791): Test disabled.
-- (void)DISABLED_testRestoreHistoryToNTPAndNavigateForward {
+- (void)testRestoreHistoryToNTPAndNavigateForward {
   GREYAssertTrue(self.testServer->Start(), @"Test server failed to start.");
   const GURL destinationURL = self.testServer->GetURL(kSimpleFileBasedTestURL);
   [ChromeEarlGrey loadURL:destinationURL];
   [ChromeEarlGrey goBack];
 
-  [ChromeEarlGrey purgeCachedWebViewPages];
+  [ChromeEarlGrey triggerRestoreViaTabGridRemoveAllUndo];
 
   [ChromeEarlGrey goForward];
   [ChromeEarlGrey waitForWebStateContainingText:"pony"];

ios/chrome/test/earl_grey/chrome_earl_grey.h

@@ -312,6 +312,10 @@ id ExecuteJavaScript(NSString* javascript, NSError* __autoreleasing* out_error);
 // Cache-Control response header says otherwise.
 - (void)purgeCachedWebViewPages;
 
+// Simulators background, killing, and restoring the app within the limitations
+// of EG1, by simply doing a tab grid close all / undo / done.
+- (void)triggerRestoreViaTabGridRemoveAllUndo;
+
 #pragma mark - Bookmarks Utilities (EG2)
 
 // Waits for the bookmark internal state to be done loading.

ios/chrome/test/earl_grey/chrome_earl_grey.mm

@@ -11,6 +11,7 @@
 #include "base/strings/sys_string_conversions.h"
 #import "base/test/ios/wait_util.h"
 #import "ios/chrome/test/earl_grey/chrome_earl_grey_app_interface.h"
+#import "ios/chrome/test/earl_grey/chrome_matchers.h"
 #import "ios/testing/earl_grey/earl_grey_test.h"
 #import "ios/testing/nserror_util.h"
 #include "ios/web/public/test/element_selector.h"
@@ -409,6 +410,20 @@ GREY_STUB_CLASS_IN_APP_MAIN_QUEUE(ChromeEarlGreyAppInterface)
   [self waitForPageToFinishLoading];
 }
 
+- (void)triggerRestoreViaTabGridRemoveAllUndo {
+  [[EarlGrey selectElementWithMatcher:chrome_test_util::ShowTabsButton()]
+      performAction:grey_tap()];
+  [[EarlGrey selectElementWithMatcher:chrome_test_util::TabGridCloseAllButton()]
+      performAction:grey_tap()];
+  [[EarlGrey
+      selectElementWithMatcher:chrome_test_util::TabGridUndoCloseAllButton()]
+      performAction:grey_tap()];
+  [[EarlGrey selectElementWithMatcher:chrome_test_util::TabGridDoneButton()]
+      performAction:grey_tap()];
+  [self waitForRestoreSessionToFinish];
+  [self waitForPageToFinishLoading];
+}
+
 #pragma mark - Settings Utilities (EG2)
 
 - (void)setContentSettings:(ContentSetting)setting {