ART: Use a 50-deep call-stack in valgrind

Necessary to diagnose issues. Required for deep suppressions.

Test: m valgrind-test-art-host
Change-Id: I08a3379d4763d66a2ae7db1f2f500c93b0a93e90
diff --git a/build/Android.gtest.mk b/build/Android.gtest.mk
index 08b56d0..c09241a 100644
--- a/build/Android.gtest.mk
+++ b/build/Android.gtest.mk
@@ -535,6 +535,7 @@
 	  (adb shell "$(GCOV_ENV) LD_LIBRARY_PATH=$(3) ANDROID_ROOT=$(ART_GTEST_TARGET_ANDROID_ROOT) \
 	    valgrind --leak-check=full --error-exitcode=1 --workaround-gcc296-bugs=yes \
 	    --suppressions=$(ART_TARGET_TEST_DIR)/valgrind-target-suppressions.txt \
+	    --num-callers=50 \
 	    $(ART_TARGET_NATIVETEST_DIR)/$(TARGET_$(2)ARCH)/$(1) && touch $(ART_TARGET_TEST_DIR)/$(TARGET_$(2)ARCH)/$$@-$$$$PPID" \
 	  && (adb pull $(ART_TARGET_TEST_DIR)/$(TARGET_$(2)ARCH)/$$@-$$$$PPID /tmp/ \
 	      && $$(call ART_TEST_PASSED,$$@)) \
@@ -591,7 +592,8 @@
 	$(hide) $$(call ART_TEST_SKIP,$$@) && \
 	  VALGRIND_LIB=$(HOST_OUT)/lib64/valgrind \
 	  $(HOST_OUT_EXECUTABLES)/valgrind --leak-check=full --error-exitcode=1 \
-	    --suppressions=art/test/valgrind-suppressions.txt $$< && \
+	    --suppressions=art/test/valgrind-suppressions.txt --num-callers=50 \
+	    $$< && \
 	    $$(call ART_TEST_PASSED,$$@) || $$(call ART_TEST_FAILED,$$@)
 
   ART_TEST_HOST_VALGRIND_GTEST$$($(2)ART_PHONY_TEST_HOST_SUFFIX)_RULES += valgrind-$$(gtest_rule)