Add global GCOV_PREFIX option.

When native coverage is enabled, add a global GCOV_PREFIX
environment variable specifying that gcda files be output
with path prefix /data/local/tmp.

Bug: 35635587
Test: make NATIVE_COVERAGE=true; check init.environ.rc
Change-Id: I40972aea3ca3168d0687bdc93e9d4b7b3a1071b9
diff --git a/rootdir/Android.mk b/rootdir/Android.mk
index 7d0c87d..03f878a 100644
--- a/rootdir/Android.mk
+++ b/rootdir/Android.mk
@@ -116,6 +116,12 @@
   EXPORT_GLOBAL_ASAN_OPTIONS := export ASAN_OPTIONS include=/system/asan.options
   LOCAL_REQUIRED_MODULES := asan.options $(ASAN_OPTIONS_FILES)
 endif
+
+EXPORT_GLOBAL_GCOV_OPTIONS :=
+ifeq ($(NATIVE_COVERAGE),true)
+  EXPORT_GLOBAL_GCOV_OPTIONS := export GCOV_PREFIX /data/misc/gcov
+endif
+
 # Put it here instead of in init.rc module definition,
 # because init.rc is conditionally included.
 #
@@ -163,6 +169,7 @@
 	$(hide) sed -e 's?%BOOTCLASSPATH%?$(PRODUCT_BOOTCLASSPATH)?g' $< >$@
 	$(hide) sed -i -e 's?%SYSTEMSERVERCLASSPATH%?$(PRODUCT_SYSTEM_SERVER_CLASSPATH)?g' $@
 	$(hide) sed -i -e 's?%EXPORT_GLOBAL_ASAN_OPTIONS%?$(EXPORT_GLOBAL_ASAN_OPTIONS)?g' $@
+	$(hide) sed -i -e 's?%EXPORT_GLOBAL_GCOV_OPTIONS%?$(EXPORT_GLOBAL_GCOV_OPTIONS)?g' $@
 
 bcp_md5 :=
 bcp_dep :=