Fix accessibility crash on < L devices

This patch adds an API util method that simply does not run the
setAccessibilityTraversalBefore method on devices that are running
Android versions < L.

Bug: 881400
Change-Id: Ie29a7f8f96e87661d0543fe99ca9e5f1a18f468f
Reviewed-on: https://chromium-review.googlesource.com/1211103Reviewed-by: agrieve <agrieve@chromium.org>
Reviewed-by: Theresa <twellington@chromium.org>
Commit-Queue: Matthew Jones <mdjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589288}

base/android/java/src/org/chromium/base/ApiCompatibilityUtils.java

@@ -702,4 +702,13 @@ public class ApiCompatibilityUtils {
         options.setLaunchDisplayId(displayId);
         return options.toBundle();
     }
+
+    /**
+     * @see View#setAccessibilityTraversalBefore(int)
+     */
+    public static void setAccessibilityTraversalBefore(View view, int viewFocusedAfter) {
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP_MR1) {
+            view.setAccessibilityTraversalBefore(viewFocusedAfter);
+        }
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarManager.java

@@ -23,6 +23,7 @@ import android.view.View;
 import android.view.View.OnAttachStateChangeListener;
 import android.view.View.OnClickListener;
 
+import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.base.Callback;
 import org.chromium.base.ThreadUtils;
 import org.chromium.base.VisibleForTesting;
@@ -892,8 +893,8 @@ public class ToolbarManager implements ToolbarTabController, UrlFocusChangeListe
                 maybeShowDuetHelpBubble(currentTab);
 
                 // Allow the bottom toolbar to be focused in accessibility after the top toolbar.
-                mLocationBar.getContainerView().setAccessibilityTraversalBefore(
-                        R.id.bottom_toolbar);
+                ApiCompatibilityUtils.setAccessibilityTraversalBefore(
+                        mLocationBar.getContainerView(), R.id.bottom_toolbar);
             }
 
             onNativeLibraryReady();