Add skeleton of input flinger.

Change-Id: I7f25080e446d4d3d9de9b18fe432a09bc751e0d9
diff --git a/libs/input/Android.mk b/libs/input/Android.mk
index 2a1e762..997ce3a 100644
--- a/libs/input/Android.mk
+++ b/libs/input/Android.mk
@@ -29,6 +29,7 @@
 
 deviceSources := \
     $(commonSources) \
+    IInputFlinger.cpp \
     InputTransport.cpp \
     VelocityControl.cpp \
     VelocityTracker.cpp