hwcomposer: Add support for UI mirroring

- Uevent observer as part of Hwcomposer
- HPD, enabling/disabling external display from HWC

Change-Id: I52b4f30c78e98c5b52c86722046389f458c2dbee
diff --git a/libhwcomposer/hwc_uimirror.h b/libhwcomposer/hwc_uimirror.h
new file mode 100644
index 0000000..af43848
--- /dev/null
+++ b/libhwcomposer/hwc_uimirror.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * Copyright (C) 2012, Code Aurora Forum. All rights reserved.
+ *
+ * Not a Contribution, Apache license notifications and license are
+ * retained for attribution purposes only.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef HWC_UIMIRROR_H
+#define HWC_UIMIRROR_H
+#include "hwc_utils.h"
+
+#define LIKELY( exp )       (__builtin_expect( (exp) != 0, true  ))
+#define UNLIKELY( exp )     (__builtin_expect( (exp) != 0, false ))
+
+namespace qhwc {
+//Feature for Mirroring UI on the External display
+class UIMirrorOverlay {
+    public:
+        // Sets up members and prepares overlay if conditions are met
+        static bool prepare(hwc_context_t *ctx, hwc_layer_list_t *list);
+        // Draws layer if this feature is on
+        static bool draw(hwc_context_t *ctx);
+    private:
+        //Configures overlay
+        static bool configure(hwc_context_t *ctx, hwc_layer_list_t *list);
+        //The chosen overlay state.
+        static ovutils::eOverlayState sState;
+        //Flags if this feature is on.
+        static bool sIsUiMirroringOn;
+};
+
+}; //namespace qhwc
+
+#endif //HWC_UIMIRROR_H