Allow forcing AAPT2 on

Building with FORCE_AAPT2=true will turn on AAPT2 for all modules
unless they set LOCAL_USE_AAPT2 := false.  The build system will
attempt to rewrite common AAPT patterns into AAPT2 patterns,
including removing --extra-packages for support library packages,
removing LOCAL_RESOURCE_DIR point to support library resources,
adding a default empty manifest file if it doesn't exist, and
converting LOCAL_STATIC_JAVA_AAR_LIBRARIES to
LOCAL_STATIC_ANDROID_LIBRARIES.

Bug: 79481102
Test: m checkbuild
Change-Id: I8d9d55fe4d5d5c965c64b0407efe74e0afc35c3a
diff --git a/core/java.mk b/core/java.mk
index 297f0b7..8e5fd1d 100644
--- a/core/java.mk
+++ b/core/java.mk
@@ -444,7 +444,7 @@
 common_proguard_flags += -dontshrink # don't shrink tests by default
 endif # test package
 ifneq ($(LOCAL_PROGUARD_ENABLED),custom)
-  ifdef LOCAL_USE_AAPT2
+  ifeq ($(LOCAL_USE_AAPT2),true)
     common_proguard_flag_files += $(foreach l,$(LOCAL_STATIC_ANDROID_LIBRARIES),\
         $(call intermediates-dir-for,JAVA_LIBRARIES,$(l),,COMMON)/export_proguard_flags)
   endif