Revert "Remove unused methods in AccessibilityUtil."

This reverts commit 445e3f42.

Reason for revert:
This broke the x86 and x86_64 builds (see bug):

797/85913] ACTION //chrome/android:chrome_java__lint(//build/toolchain/android:android_clang_x64)
FAILED: gen/chrome/android/chrome_java__lint/result.xml gen/chrome/android/chrome_java__lint/config.xml
python ../../build/android/gyp/lint.py --lint-path ../../third_party/android_sdk/public/tools-lint/b...(too long)

../resource_zips/chrome/android/chrome_strings_grd.resources.zip/values/android_chrome_strings.xml:679 The resource `R.string.update_from_market` appears to be unused: UnusedResources [warning]
<string name="update_from_market">"Update"</string>
~~~~~~~~~~~~~~~~~~~~~~~~~

Original change's description:
> Remove unused methods in AccessibilityUtil.
> 
> These methods were added for crbug.com/358708 but the usage was
> reverted shortly after and they were not cleaned up.
> 
> Bug: 995916
> Change-Id: I63a4ec3756e34b56e1cccb54cbc7cf1bb9c312ad
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1808082
> Reviewed-by: Theresa  <twellington@chromium.org>
> Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
> Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#697363}

TBR=dmazzoni@chromium.org,twellington@chromium.org,hnakashima@chromium.org

Change-Id: Idf10d1a28b5c0cf5dfd13edf697451966eea64bb
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 995916, 1005188
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1810525Reviewed-by: Hans Wennborg <hans@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#697568}

chrome/android/java/src/org/chromium/chrome/browser/util/AccessibilityUtil.java

@@ -8,7 +8,11 @@ import android.accessibilityservice.AccessibilityServiceInfo;
 import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.content.Context;
+import android.content.DialogInterface;
+import android.content.Intent;
+import android.net.Uri;
 import android.os.Build;
+import android.support.v7.app.AlertDialog;
 import android.view.Gravity;
 import android.view.View;
 import android.view.accessibility.AccessibilityManager;
@@ -17,7 +21,10 @@ import org.chromium.base.ActivityState;
 import org.chromium.base.ApplicationStatus;
 import org.chromium.base.ApplicationStatus.ActivityStateListener;
 import org.chromium.base.ContextUtils;
+import org.chromium.base.PackageUtils;
 import org.chromium.base.TraceEvent;
+import org.chromium.chrome.R;
+import org.chromium.ui.UiUtils;
 import org.chromium.ui.widget.Toast;
 
 import java.util.List;
@@ -26,6 +33,21 @@ import java.util.List;
  * Exposes information about the current accessibility state
  */
 public class AccessibilityUtil {
+    // Whether we've already shown an alert that they have an old version of TalkBack running.
+    private static boolean sOldTalkBackVersionAlertShown;
+
+    // The link to download or update TalkBack from the Play Store.
+    private static final String TALKBACK_MARKET_LINK =
+            "market://search?q=pname:com.google.android.marvin.talkback";
+
+    // The package name for TalkBack, an Android accessibility service.
+    private static final String TALKBACK_PACKAGE_NAME =
+            "com.google.android.marvin.talkback";
+
+    // The minimum TalkBack version that we support. This is the version that shipped with
+    // KitKat, from fall 2013. Versions older than that should be updated.
+    private static final int MIN_TALKBACK_VERSION = 105;
+
     private static Boolean sIsAccessibilityEnabled;
     private static ActivityStateListener sActivityStateListener;
 
@@ -93,7 +115,7 @@ public class AccessibilityUtil {
     }
 
     /**
-     * Checks whether the given {@link AccessibilityServiceInfo} can perform gestures.
+     * Checks whether the given {@link AccesibilityServiceInfo} can perform gestures.
      * @param service The service to check.
      * @return Whether the {@code service} can perform gestures. On N+, this relies on the
      *         capabilities the service can perform. On L & M, this looks specifically for
@@ -111,6 +133,69 @@ public class AccessibilityUtil {
         return false;
     }
 
+    /**
+     * Checks to see if an old version of TalkBack is running that Chrome doesn't support,
+     * and if so, shows an alert dialog prompting the user to update the app.
+     * @param context A {@link Context} instance.
+     * @return        True if the dialog was shown.
+     */
+    public static boolean showWarningIfOldTalkbackRunning(Context context) {
+        AccessibilityManager manager = (AccessibilityManager)
+                context.getSystemService(Context.ACCESSIBILITY_SERVICE);
+        if (manager == null) return false;
+
+        boolean isTalkbackRunning = false;
+        try {
+            List<AccessibilityServiceInfo> services =
+                    manager.getEnabledAccessibilityServiceList(
+                            AccessibilityServiceInfo.FEEDBACK_SPOKEN);
+            for (AccessibilityServiceInfo service : services) {
+                if (service.getId().contains(TALKBACK_PACKAGE_NAME)) isTalkbackRunning = true;
+            }
+        } catch (NullPointerException e) {
+            // getEnabledAccessibilityServiceList() can throw an NPE due to a bad
+            // AccessibilityService.
+        }
+        if (!isTalkbackRunning) return false;
+
+        if (PackageUtils.getPackageVersion(context, TALKBACK_PACKAGE_NAME) < MIN_TALKBACK_VERSION
+                && !sOldTalkBackVersionAlertShown) {
+            showOldTalkbackVersionAlertOnce(context);
+            return true;
+        }
+
+        return false;
+    }
+
+    private static void showOldTalkbackVersionAlertOnce(final Context context) {
+        if (sOldTalkBackVersionAlertShown) return;
+        sOldTalkBackVersionAlertShown = true;
+
+        AlertDialog.Builder builder =
+                new UiUtils
+                        .CompatibleAlertDialogBuilder(context, R.style.Theme_Chromium_AlertDialog)
+                        .setTitle(R.string.old_talkback_title)
+                        .setPositiveButton(R.string.update_from_market,
+                                new DialogInterface.OnClickListener() {
+                                    @Override
+                                    public void onClick(DialogInterface dialog, int id) {
+                                        Uri marketUri = Uri.parse(TALKBACK_MARKET_LINK);
+                                        Intent marketIntent =
+                                                new Intent(Intent.ACTION_VIEW, marketUri);
+                                        context.startActivity(marketIntent);
+                                    }
+                                })
+                        .setNegativeButton(R.string.cancel_talkback_alert,
+                                new DialogInterface.OnClickListener() {
+                                    @Override
+                                    public void onClick(DialogInterface dialog, int id) {
+                                        // Do nothing, this alert is only shown once either way.
+                                    }
+                                });
+        AlertDialog dialog = builder.create();
+        dialog.show();
+    }
+
     /**
      * Shows the content description toast for items on the toolbar.
      * @param context The context to use for the toast.

chrome/android/java/strings/android_chrome_strings.grd

@@ -2204,9 +2204,15 @@ To change this setting, <ph name="BEGIN_LINK">&lt;resetlink&gt;</ph>reset sync<p
       </message>
 
       <!-- TalkBack upgrade -->
+      <message name="IDS_OLD_TALKBACK_TITLE" desc="Title of dialog notifying user that the version of TalkBack they're running is too old.">
+        You need to update TalkBack to a newer version.
+      </message>
       <message name="IDS_UPDATE_FROM_MARKET" desc="Title of button that will direct the user to update TalkBack from the market (Play Store)">
         Update
       </message>
+      <message name="IDS_CANCEL_TALKBACK_ALERT" desc="Title of button that will cancel the TalkBack alert dialog dialog.">
+        Cancel
+      </message>
 
       <!-- Android NFC Beam strings -->
       <message name="IDS_NFC_BEAM_ERROR_OVERLAY_ACTIVE" desc="Android Beam error - a tab is not in the foreground [CHAR-LIMIT=40]">