[WIP] Add Chromium-side support for the Screen Orientation API

content/browser/screen_orientation/screen_orientation_provider_android.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "content/browser/screen_orientation/screen_orientation_provider_android.h"
+
+#include "content/browser/screen_orientation/screen_orientation_dispatcher_host.h"
+#include "jni/ScreenOrientationProvider_jni.h"
+
+using base::android::AttachCurrentThread;
+
+namespace content {
+
+ScreenOrientationProviderAndroid::ScreenOrientationProviderAndroid() {
+
+}
+
+ScreenOrientationProviderAndroid::~ScreenOrientationProviderAndroid() {
+
+}
+
+bool ScreenOrientationProviderAndroid::LockOrientation(
+        Orientations orientations) {
+
+  if ((orientations & OrientationPortrait) &&
+      (orientations & OrientationLandscape))
+    return false;

[kenneth.r.christiansen, 2014/02/06 15:03:12]

does the spec say that that is not allowed?

I heard that some android phones disallow portrait-secondary by default, but
that apps can actually override that. If that is the case I would say that this
should be allowed. Unlock will restore default platform behavior

[ostap, 2014/02/06 21:23:28]

That's android specific.
Current android API can lock only one current orientation, so locking landscape
and portrait at the same time won't work for sure.

+
+  if (j_orientation_provider_.is_null()) {
+    j_orientation_provider_.Reset(
+        Java_ScreenOrientationProvider_create(
+            AttachCurrentThread(),
+            base::android::GetApplicationContext()));
+  }
+
+  Java_ScreenOrientationProvider_lockOrientation(AttachCurrentThread(),
+      j_orientation_provider_.obj(), orientations);
+  return true;
+}
+
+void ScreenOrientationProviderAndroid::UnlockOrientation() {
+  if (j_orientation_provider_.is_null())
+    return;
+  Java_ScreenOrientationProvider_unlockOrientation(AttachCurrentThread(),
+      j_orientation_provider_.obj());
+
+}
+
+// static
+bool ScreenOrientationProviderAndroid::Register(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+// static
+ScreenOrientationProvider* ScreenOrientationDispatcherHost::CreateProvider() {
+  return new ScreenOrientationProviderAndroid();
+}
+
+}  // namespace content