Added native functionality to create a color layer.

Added a new layer that can draw a specified color and specified
alpha. This will replace creating a dim layer and allow any colors,
not just black, to be set for this layer.

Test: Added tests to Transaction_test.cpp to test with a color
      and a color layer with alpha.

Change-Id: I00a38d1bbc01093026f088c3347454281bdc2b8c
diff --git a/libs/gui/LayerState.cpp b/libs/gui/LayerState.cpp
index 3418a49..fcee73f 100644
--- a/libs/gui/LayerState.cpp
+++ b/libs/gui/LayerState.cpp
@@ -46,6 +46,9 @@
     output.writeStrongBinder(IInterface::asBinder(barrierGbp));
     output.writeStrongBinder(relativeLayerHandle);
     output.writeStrongBinder(parentHandleForChild);
+    output.writeFloat(color.r);
+    output.writeFloat(color.g);
+    output.writeFloat(color.b);
     output.write(transparentRegion);
     return NO_ERROR;
 }
@@ -79,6 +82,9 @@
         interface_cast<IGraphicBufferProducer>(input.readStrongBinder());
     relativeLayerHandle = input.readStrongBinder();
     parentHandleForChild = input.readStrongBinder();
+    color.r = input.readFloat();
+    color.g = input.readFloat();
+    color.b = input.readFloat();
     input.read(transparentRegion);
     return NO_ERROR;
 }