Add support for LOCAL_JAVACFLAGS

The Dalvik core libraries team would like to start making warnings
errors in certain packages by definition LOCAL_JAVACFLAGS. This will
allow easier debuging of warnings in other packages by supplying
"-Xlint:..."  options.
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 58c1800..6107808 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -51,6 +51,7 @@
 LOCAL_PREBUILT_STATIC_JAVA_LIBRARIES:=
 LOCAL_PREBUILT_STRIP_COMMENTS:=
 LOCAL_INTERMEDIATE_SOURCES:=
+LOCAL_JAVACFLAGS:=
 LOCAL_JAVA_LIBRARIES:=
 LOCAL_NO_STANDARD_LIBRARIES:=
 LOCAL_CLASSPATH:=