Collect metrics on running Accessibility services on Android

content/public/android/java/src/org/chromium/content/browser/accessibility/KitKatBrowserAccessibilityManager.java

Index: content/public/android/java/src/org/chromium/content/browser/accessibility/KitKatBrowserAccessibilityManager.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/accessibility/KitKatBrowserAccessibilityManager.java b/content/public/android/java/src/org/chromium/content/browser/accessibility/KitKatBrowserAccessibilityManager.java
index 58ea5d88c83ed70b5fc0eafcb06ca42c44c9e0fc..759c582083cd3f893da634808b1e938d9dcbd2cc 100644
--- a/content/public/android/java/src/org/chromium/content/browser/accessibility/KitKatBrowserAccessibilityManager.java
+++ b/content/public/android/java/src/org/chromium/content/browser/accessibility/KitKatBrowserAccessibilityManager.java
@@ -4,6 +4,7 @@
 
 package org.chromium.content.browser.accessibility;
 
+import android.accessibilityservice.AccessibilityServiceInfo;
 import android.annotation.TargetApi;
 import android.os.Build;
 import android.os.Bundle;
@@ -42,4 +43,15 @@ public class KitKatBrowserAccessibilityManager extends BrowserAccessibilityManag
             node.setTextSelection(selectionStartIndex, selectionEndIndex);
         }
     }
+
+    @Override
+    protected int getAccessibilityServiceCapabilitiesMask() {
+        int capabilitiesMask = 0;
+        for (AccessibilityServiceInfo service :
+                mAccessibilityManager.getEnabledAccessibilityServiceList(
+                        AccessibilityServiceInfo.FEEDBACK_ALL_MASK)) {
+            capabilitiesMask |= service.getCapabilities();
+        }
+        return capabilitiesMask;
+    }
 }