Revert "Add AX ID for Cancel and Done button on Translate Language Picker."

This reverts commit b9e3aebd.

Reason for revert: I think this is breaking TranslateTestCase.testLanguageDetectionInfobar. I cannot reproduce the error locally.

Original change's description:
> Add AX ID for Cancel and Done button on Translate Language Picker.
> 
> Currently, the test uses the following matchers to find the cancel and
> done button on language picker:
> 
> grey_allOf(chrome_test_util::ButtonWithAccessibilityLabel(@"Cancel"),
>                     grey_userInteractionEnabled(), nil);
> 
> This is not bullet proof and may break any time, and this CL fixes the
> issue by adding AX ID to both the cancel and done buttons.
> 
> Bug: 750344
> Change-Id: I4fda45961b684b877adf29a5bf0fee6e03f1ba8d
> Reviewed-on: https://chromium-review.googlesource.com/594831
> Reviewed-by: Eugene But <eugenebut@chromium.org>
> Commit-Queue: Yuke Liao <liaoyuke@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#490840}

TBR=eugenebut@chromium.org,liaoyuke@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 750344
Change-Id: Ibb4f68af8e0c502000d063d6b19ff185fc1b1a42
Reviewed-on: https://chromium-review.googlesource.com/597627Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#491327}

ios/chrome/browser/translate/before_translate_infobar_controller.h

@@ -7,12 +7,6 @@
 
 #include "ios/chrome/browser/infobars/infobar_controller.h"
 
-// The accessibility identifier of the cancel button on language picker view.
-extern NSString* const kLanguagePickerCancelButtonId;
-
-// The accessibility identifier of the done button on language picker view.
-extern NSString* const kLanguagePickerDoneButtonId;
-
 @interface BeforeTranslateInfoBarController : InfoBarController
 
 @end

ios/chrome/browser/translate/before_translate_infobar_controller.mm

@@ -22,9 +22,6 @@
 #error "This file requires ARC support."
 #endif
 
-NSString* const kLanguagePickerCancelButtonId = @"LanguagePickerCancelButton";
-NSString* const kLanguagePickerDoneButtonId = @"LanguagePickerDoneButton";
-
 namespace {
 
 CGFloat kNavigationBarHeight = 44;
@@ -305,12 +302,10 @@ NSTimeInterval kPickerAnimationDurationInSeconds = 0.2;
       initWithBarButtonSystemItem:UIBarButtonSystemItemDone
                            target:self
                            action:@selector(languageSelectionDone)];
-  [doneButton setAccessibilityIdentifier:kLanguagePickerDoneButtonId];
   UIBarButtonItem* cancelButton = [[UIBarButtonItem alloc]
       initWithBarButtonSystemItem:UIBarButtonSystemItemCancel
                            target:self
                            action:@selector(dismissLanguageSelectionView)];
-  [cancelButton setAccessibilityIdentifier:kLanguagePickerCancelButtonId];
   UINavigationItem* item = [[UINavigationItem alloc] initWithTitle:@""];
   [item setRightBarButtonItem:doneButton];
   [item setLeftBarButtonItem:cancelButton];

ios/chrome/browser/translate/translate_egtest.mm

@@ -19,7 +19,6 @@
 #import "components/translate/ios/browser/js_translate_manager.h"
 #import "components/translate/ios/browser/language_detection_controller.h"
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
-#include "ios/chrome/browser/translate/before_translate_infobar_controller.h"
 #include "ios/chrome/browser/translate/chrome_ios_translate_client.h"
 #import "ios/chrome/test/app/chrome_test_util.h"
 #import "ios/chrome/test/app/tab_test_util.h"
@@ -108,6 +107,20 @@ NSString* GetTranslateInfobarSwitchLabel(const std::string& language) {
       IDS_TRANSLATE_INFOBAR_ALWAYS_TRANSLATE, base::UTF8ToUTF16(language)));
 }
 
+// Returns a matcher for the button with label "Cancel" in the language picker.
+// TODO(crbug.com/750344): Change the matcher to use accessibility ID.
+id<GREYMatcher> LanguagePickerCancelButton() {
+  return grey_allOf(chrome_test_util::ButtonWithAccessibilityLabel(@"Cancel"),
+                    grey_userInteractionEnabled(), nil);
+}
+
+// Returns a matcher for the button with label "Done" in the language picker.
+// TODO(crbug.com/750344): Change the matcher to use accessibility ID.
+id<GREYMatcher> LanguagePickerDoneButton() {
+  return grey_allOf(chrome_test_util::ButtonWithAccessibilityLabel(@"Done"),
+                    grey_userInteractionEnabled(), nil);
+}
+
 #pragma mark - TestResponseProvider
 
 // A ResponseProvider that provides html responses of texts in different
@@ -602,8 +615,9 @@ using translate::LanguageDetectionController;
       selectElementWithMatcher:chrome_test_util::ButtonWithAccessibilityLabel(
                                    kFrench)] performAction:grey_tap()];
 
-  [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
-                                          kLanguagePickerCancelButtonId)]
+  // The language picker uses the system accessibility labels (thus no
+  // IDS_CANCEL here).
+  [[EarlGrey selectElementWithMatcher:LanguagePickerCancelButton()]
       assertWithMatcher:grey_notNil()];
 
   // Change the language using the picker.
@@ -614,8 +628,7 @@ using translate::LanguageDetectionController;
   [[EarlGrey selectElementWithMatcher:languageMatcher]
       performAction:grey_tap()];
 
-  [[EarlGrey selectElementWithMatcher:grey_accessibilityID(
-                                          kLanguagePickerDoneButtonId)]
+  [[EarlGrey selectElementWithMatcher:LanguagePickerDoneButton()]
       performAction:grey_tap()];
   [[EarlGrey
       selectElementWithMatcher:chrome_test_util::ButtonWithAccessibilityLabel(