libledservice-common depends on libbinder

Also export libbinder's headers, since you need them to include
headers from libledservice-common.

Bug: 27804373
Change-Id: I42b58408fd4eeab3e0d277bb5771a6507ba1d90d
Test: Compiles.
diff --git a/src/common/Android.mk b/src/common/Android.mk
index 2721cd6..3bb7b5d 100644
--- a/src/common/Android.mk
+++ b/src/common/Android.mk
@@ -18,6 +18,8 @@
 LOCAL_MODULE := libledservice-common
 LOCAL_AIDL_INCLUDES := $(LOCAL_PATH)/aidl
 LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)
+LOCAL_EXPORT_SHARED_LIBRARY_HEADERS := libbinder
+LOCAL_SHARED_LIBRARIES := libbinder
 
 LOCAL_SRC_FILES := \
 	aidl/brillo/examples/ledflasher/ILEDService.aidl \