Download infobar : Fix for accessibility

The talkback doesn't announce the subsequent text updates to the infobar
with the default infobar implementation. With this CL we are trying to fix that.

Bug: 848135
Change-Id: I49c671fee841026129ed244df420e5e1fc25e75b
Reviewed-on: https://chromium-review.googlesource.com/1087759Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Shakti Sahu <shaktisahu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565752}

chrome/android/java/src/org/chromium/chrome/browser/download/DownloadInfoBarController.java

@@ -110,6 +110,7 @@ public class DownloadInfoBarController implements OfflineContentProvider.Observe
         public ContentId id;
 
         public String message;
+        public String accessibilityMessage;
         public String link;
         public int icon;
 
@@ -618,6 +619,8 @@ public class DownloadInfoBarController implements OfflineContentProvider.Observe
         }
 
         setForceReparent(info);
+        setAccessibilityMessage(
+                info, showAccelerating && infoBarState == DownloadInfoBarState.DOWNLOADING);
         showInfoBar(infoBarState, info);
     }
 
@@ -627,6 +630,15 @@ public class DownloadInfoBarController implements OfflineContentProvider.Observe
                 mCurrentInfo == null ? null : mCurrentInfo.downloadCount);
     }
 
+    private void setAccessibilityMessage(
+            DownloadProgressInfoBarData info, boolean showAccelerating) {
+        info.accessibilityMessage = info.message;
+        if (!showAccelerating) {
+            info.accessibilityMessage = info.accessibilityMessage + " "
+                    + getContext().getString(R.string.bottom_bar_screen_position);
+        }
+    }
+
     private void clearEndTimerRunnable() {
         mHandler.removeCallbacks(mEndTimerRunnable);
         mEndTimerRunnable = null;

chrome/android/java/src/org/chromium/chrome/browser/infobar/DownloadProgressInfoBar.java

@@ -8,8 +8,12 @@ import android.graphics.drawable.Drawable;
 import android.support.annotation.Nullable;
 import android.support.graphics.drawable.Animatable2Compat;
 import android.support.graphics.drawable.AnimatedVectorDrawableCompat;
+import android.support.v4.view.ViewCompat;
+import android.view.View;
+import android.widget.TextView;
 
 import org.chromium.base.annotations.CalledByNative;
+import org.chromium.chrome.R;
 import org.chromium.chrome.browser.download.DownloadInfoBarController;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.components.offline_items_collection.ContentId;
@@ -110,6 +114,11 @@ public class DownloadProgressInfoBar extends InfoBar {
         layout.setMessage(mInfo.message);
         layout.appendMessageLinkText(mInfo.link);
 
+        TextView messageView =
+                (TextView) layout.getMessageLayout().findViewById(R.id.infobar_message);
+        messageView.setContentDescription(mInfo.accessibilityMessage);
+        ViewCompat.setAccessibilityLiveRegion(messageView, View.ACCESSIBILITY_LIVE_REGION_POLITE);
+
         if (!mInfo.hasAnimation) {
             layout.getIcon().setImageResource(mInfo.icon);
             return;
@@ -151,6 +160,11 @@ public class DownloadProgressInfoBar extends InfoBar {
         setLayoutProperties((InfoBarLayout) getView(), info);
     }
 
+    @Override
+    public CharSequence getAccessibilityText() {
+        return null;
+    }
+
     /**
      * Creates and shows the {@link DownloadProgressInfoBar}.
      * @param tab The tab that the {@link DownloadProgressInfoBar} should be shown in.

chrome/android/java/src/org/chromium/chrome/browser/infobar/InfoBarContainerLayout.java

@@ -12,6 +12,7 @@ import android.animation.ValueAnimator;
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.res.Resources;
+import android.text.TextUtils;
 import android.view.Gravity;
 import android.view.MotionEvent;
 import android.view.View;
@@ -865,6 +866,12 @@ public class InfoBarContainerLayout extends FrameLayout {
         mFloatingBehavior.afterOnMeasure(getMeasuredHeight());
     }
 
+    @Override
+    public void announceForAccessibility(CharSequence text) {
+        if (TextUtils.isEmpty(text)) return;
+        super.announceForAccessibility(text);
+    }
+
     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
         super.onLayout(changed, left, top, right, bottom);