Suppress implicit-fallthrough warnings.

Add FALLTHROUGH_INTENDED for clang compiler.

Bug: 112564944
Test: build with global -Wimplicit-fallthrough.
Change-Id: I40f8bbf94e207c9dd90921e9b762ba51abab5777
diff --git a/libpixelflinger/Android.mk b/libpixelflinger/Android.mk
index 14883f4..8c80f6a 100644
--- a/libpixelflinger/Android.mk
+++ b/libpixelflinger/Android.mk
@@ -73,6 +73,7 @@
 LOCAL_CFLAGS := $(PIXELFLINGER_CFLAGS)
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
 LOCAL_C_INCLUDES += $(LOCAL_EXPORT_C_INCLUDE_DIRS)
+LOCAL_HEADER_LIBRARIES := libbase_headers
 LOCAL_SHARED_LIBRARIES := libcutils liblog libutils
 
 include $(BUILD_SHARED_LIBRARY)