[Android WebView] Enable spatial navigation / DPAD

Turn on the --enable-spatial-navigation flag, and also bubble up
unhandled DPAD events to the neighboring views in the view tree.
Likewise, WebContentsDelegate::TakeFocus() bubble to logical next
or previous neighbor view.

Also disabled the FileSystem API while in the area updating flags.

BUG=286698

Review URL: https://chromiumcodereview.appspot.com/23619024

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221946 0039d316-1c4b-4281-b951-d872f2087c98

android_webview/java/src/org/chromium/android_webview/AwContents.java

@@ -490,7 +490,7 @@ public class AwContents {
         mLayoutSizer.setDelegate(new AwLayoutSizerDelegate());
         mLayoutSizer.setDIPScale(mDIPScale);
         mWebContentsDelegate = new AwWebContentsDelegateAdapter(contentsClient,
-                mLayoutSizer.getPreferredSizeChangedListener());
+                mLayoutSizer.getPreferredSizeChangedListener(), mContainerView);
         mContentsClientBridge = new AwContentsClientBridge(contentsClient);
         mZoomControls = new AwZoomControls(this);
         mIoThreadClient = new IoThreadClientImpl();

android_webview/java/src/org/chromium/android_webview/AwWebContentsDelegateAdapter.java

@@ -10,6 +10,7 @@ import android.os.Looper;
 import android.os.Message;
 import android.util.Log;
 import android.view.KeyEvent;
+import android.view.View;
 import android.webkit.ConsoleMessage;
 import android.webkit.ValueCallback;
 
@@ -37,11 +38,14 @@ class AwWebContentsDelegateAdapter extends AwWebContentsDelegate {
 
     final AwContentsClient mContentsClient;
     final PreferredSizeChangedListener mPreferredSizeChangedListener;
+    final View mContainerView;
 
     public AwWebContentsDelegateAdapter(AwContentsClient contentsClient,
-            PreferredSizeChangedListener preferredSizeChangedListener) {
+            PreferredSizeChangedListener preferredSizeChangedListener,
+            View containerView) {
         mContentsClient = contentsClient;
         mPreferredSizeChangedListener = preferredSizeChangedListener;
+        mContainerView = containerView;
     }
 
     @Override
@@ -51,9 +55,45 @@ class AwWebContentsDelegateAdapter extends AwWebContentsDelegate {
 
     @Override
     public void handleKeyboardEvent(KeyEvent event) {
+        if (event.getAction() == KeyEvent.ACTION_DOWN) {
+            int direction;
+            switch (event.getKeyCode()) {
+                case KeyEvent.KEYCODE_DPAD_DOWN:
+                    direction = View.FOCUS_DOWN;
+                    break;
+                case KeyEvent.KEYCODE_DPAD_UP:
+                    direction = View.FOCUS_UP;
+                    break;
+                case KeyEvent.KEYCODE_DPAD_LEFT:
+                    direction = View.FOCUS_LEFT;
+                    break;
+                case KeyEvent.KEYCODE_DPAD_RIGHT:
+                    direction = View.FOCUS_RIGHT;
+                    break;
+                default:
+                    direction = 0;
+                    break;
+            }
+            if (direction != 0 && tryToMoveFocus(direction)) return;
+        }
         mContentsClient.onUnhandledKeyEvent(event);
     }
 
+    @Override
+    public boolean takeFocus(boolean reverse) {
+        int direction =
+            (reverse == (mContainerView.getLayoutDirection() == View.LAYOUT_DIRECTION_RTL)) ?
+            View.FOCUS_RIGHT : View.FOCUS_LEFT;
+        if (tryToMoveFocus(direction)) return true;
+        direction = reverse ? View.FOCUS_UP : View.FOCUS_DOWN;
+        return tryToMoveFocus(direction);
+    }
+
+    private boolean tryToMoveFocus(int direction) {
+        View focus = mContainerView.focusSearch(direction);
+        return focus != null && focus != mContainerView && focus.requestFocus();
+    }
+
     @Override
     public boolean addMessageToConsole(int level, String message, int lineNumber,
             String sourceId) {

android_webview/lib/main/aw_main_delegate.cc

@@ -64,6 +64,14 @@ bool AwMainDelegate::BasicStartupComplete(int* exit_code) {
   // Ganesh backed 2D-Canvas is not yet working and causes crashes.
   cl->AppendSwitch(switches::kDisableAccelerated2dCanvas);
 
+  // File system API not supported (requires some new API; internal bug 6930981)
+  // TODO(joth): export and use switches::kDisableFileSystem
+  cl->AppendSwitch("disable-file-system");
+
+  // Enable D-PAD navigation for application compatibility.
+  // TODO(joth): export and use switches::EnableSpatialNavigation.
+  cl->AppendSwitch("enable-spatial-navigation");
+
   return false;
 }