[Android] Implement ScreenOrientation.unlock align with spec

This is for compliance with ScreenOrientation
(https://w3c.github.io/screen-orientation).

When unlock screen orientation, it should lock the orientation
to default orientation.
Previous implementation is to set the orientation to "unspecified",
which is not fully aligned with spec.

Instead, read the configuration from the activity metadata in
AndroidManifest.xml and set the orientation accordingly.

BUG=394214

Review URL: https://codereview.chromium.org/399553002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@284396 0039d316-1c4b-4281-b951-d872f2087c98
(cherry picked from commit 11420f5)

AUTHORS

@@ -355,6 +355,7 @@ Sevan Janiyan <[email protected]>
 ShankarGanesh K <[email protected]>
 Shez Baig <[email protected]>
 Shiliu Wang <[email protected]>
+Shiliu Wang <[email protected]>
 Shouqun Liu <[email protected]>
 Shreyas VA <[email protected]>
 Simon Arlott <[email protected]>

content/public/android/java/src/org/chromium/content/browser/ScreenOrientationProvider.java

@@ -6,6 +6,7 @@
 
 import android.app.Activity;
 import android.content.pm.ActivityInfo;
+import android.content.pm.PackageManager;
 import android.util.Log;
 
 import com.google.common.annotations.VisibleForTesting;
@@ -74,7 +75,17 @@ void unlockOrientation() {
             return;
         }
 
-        activity.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED);
+        int defaultOrientation = ActivityInfo.SCREEN_ORIENTATION_UNSPECIFIED;
+
+        try {
+            ActivityInfo info = activity.getPackageManager().getActivityInfo(
+                    activity.getComponentName(), PackageManager.GET_META_DATA);
+            defaultOrientation = info.screenOrientation;
+        } catch (PackageManager.NameNotFoundException e) {
+            // Do nothing, defaultOrientation should be SCREEN_ORIENTATION_UNSPECIFIED.
+        } finally {
+            activity.setRequestedOrientation(defaultOrientation);
+        }
     }
 
     private ScreenOrientationProvider() {