Remove unused .fs file suppport

.fs files are obsolete.

Bug: 73885582
Test: m checkbuild
Change-Id: I74b618099333fe565c7b235994be64e6466d2da6
diff --git a/core/java_common.mk b/core/java_common.mk
index 8ff05d6..f9ba059 100644
--- a/core/java_common.mk
+++ b/core/java_common.mk
@@ -177,7 +177,7 @@
 #####################################
 ## Warn if there is unrecognized file in LOCAL_SRC_FILES.
 my_unknown_src_files := $(filter-out \
-  %.java %.aidl %.proto %.logtags %.fs %.rs, \
+  %.java %.aidl %.proto %.logtags %.rs, \
   $(LOCAL_SRC_FILES) $(LOCAL_INTERMEDIATE_SOURCES) $(LOCAL_GENERATED_SOURCES))
 ifneq ($(my_unknown_src_files),)
 $(warning $(LOCAL_MODULE_MAKEFILE): $(LOCAL_MODULE): Unused source files: $(my_unknown_src_files))