Revert "Add accessibility alert event when DeepScanningDialogViews changes"

This reverts commit 2e94ca8d.

Reason for revert: Failures on mac builder crbug.com/1132093

Original change's description:
> Add accessibility alert event when DeepScanningDialogViews changes
>
> This allows a screen reader to read the updated text of the dialog.
>
> Bug: 1131565
> Change-Id: I73a2df8067ffc96148ebf5d50a9412cf34b67feb
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2424841
> Commit-Queue: Dominique Fauteux-Chapleau <domfc@chromium.org>
> Reviewed-by: Roger Tawa <rogerta@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#810290}

TBR=rogerta@chromium.org,domfc@chromium.org

Change-Id: I45a93a22d5f443bb254cc4909312aeecc9aee356
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 1131565
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2429786Reviewed-by: Dan H <harringtond@chromium.org>
Commit-Queue: Dan H <harringtond@chromium.org>
Cr-Commit-Position: refs/heads/master@{#810329}

chrome/browser/safe_browsing/cloud_content_scanning/deep_scanning_dialog_views.cc

@@ -27,7 +27,6 @@
 #include "ui/gfx/paint_vector_icon.h"
 #include "ui/gfx/text_constants.h"
 #include "ui/native_theme/native_theme.h"
-#include "ui/views/accessibility/view_accessibility.h"
 #include "ui/views/background.h"
 #include "ui/views/border.h"
 #include "ui/views/bubble/bubble_frame_view.h"
@@ -352,11 +351,8 @@ void DeepScanningDialogViews::UpdateDialog() {
   // Update the buttons.
   SetupButtons();
 
-  // Update the message's text, and send an alert for screen readers since the
-  // text changed.
-  base::string16 new_message = GetDialogMessage();
-  message_->SetText(new_message);
-  message_->GetViewAccessibility().AnnounceText(std::move(new_message));
+  // Update the message's text.
+  message_->SetText(GetDialogMessage());
 
   // Resize the dialog's height. This is needed since the text might take more
   // lines after changing.

chrome/browser/safe_browsing/cloud_content_scanning/deep_scanning_dialog_views_browsertest.cc

@@ -22,7 +22,6 @@
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/throbber.h"
-#include "ui/views/test/ax_event_counter.h"
 
 namespace safe_browsing {
 
@@ -42,15 +41,13 @@ base::string16 text() {
 // - It respects time constraints (minimum shown time, initial delay, timeout)
 // - It is always destroyed, therefore |quit_closure_| is called in the dtor
 //   observer.
-// - It sends accessibility events correctly.
 class DeepScanningDialogViewsBehaviorBrowserTest
     : public DeepScanningBrowserTestBase,
       public DeepScanningDialogViews::TestObserver,
       public testing::WithParamInterface<
           std::tuple<bool, bool, base::TimeDelta>> {
  public:
-  DeepScanningDialogViewsBehaviorBrowserTest()
-      : ax_event_counter_(views::AXEventManager::Get()) {
+  DeepScanningDialogViewsBehaviorBrowserTest() {
     DeepScanningDialogViews::SetObserverForTesting(this);
 
     expected_scan_result_ = dlp_success() && malware_success();
@@ -89,11 +86,6 @@ class DeepScanningDialogViewsBehaviorBrowserTest
     // The dialog's buttons should be Cancel in the pending and fail case.
     EXPECT_EQ(dialog_->GetDialogButtons(), ui::DIALOG_BUTTON_CANCEL);
 
-    // Record the number of AX events until now to check if the text update adds
-    // one later.
-    ax_events_count_when_first_shown_ =
-        ax_event_counter_.GetCount(ax::mojom::Event::kAlert);
-
     // The dialog should only be shown once some time after being constructed.
     EXPECT_TRUE(ctor_called_);
     EXPECT_FALSE(views_first_shown_);
@@ -130,10 +122,6 @@ class DeepScanningDialogViewsBehaviorBrowserTest
     // The dialog should only be updated once some time after being shown.
     EXPECT_TRUE(views_first_shown_);
     EXPECT_FALSE(dialog_updated_);
-
-    // The dialog being updated implies an accessibility alert is sent.
-    EXPECT_EQ(ax_events_count_when_first_shown_ + 1,
-              ax_event_counter_.GetCount(ax::mojom::Event::kAlert));
     dialog_updated_ = true;
   }
 
@@ -190,9 +178,6 @@ class DeepScanningDialogViewsBehaviorBrowserTest
   bool dialog_updated_ = false;
 
   bool expected_scan_result_;
-
-  int ax_events_count_when_first_shown_ = 0;
-  views::test::AXEventCounter ax_event_counter_;
 };
 
 // Tests the behavior of the dialog in the following ways: