tsan: fix test in debug mode

sanitizer-x86_64-linux-autoconf has failed after the previous tsan commit:

FAIL: ThreadSanitizer-x86_64 :: java_finalizer2.cpp (245 of 403)
******************** TEST 'ThreadSanitizer-x86_64 :: java_finalizer2.cpp' FAILED ********************
Script:
--
: 'RUN: at line 1';      /b/sanitizer-x86_64-linux-autoconf/build/tsan_debug_build/./bin/clang  --driver-mode=g++ -fsanitize=thread -Wall  -m64   -gline-tables-only -I/b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/test/tsan/../ -std=c++11 -I/b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/test/tsan/../ -nostdinc++ -I/b/sanitizer-x86_64-linux-autoconf/build/tsan_debug_build/tools/clang/runtime/compiler-rt-bins/lib/tsan/libcxx_tsan_x86_64/include/c++/v1 -O1 /b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/test/tsan/java_finalizer2.cpp -o /b/sanitizer-x86_64-linux-autoconf/build/tsan_debug_build/tools/clang/runtime/compiler-rt-bins/test/tsan/X86_64Config/Output/java_finalizer2.cpp.tmp &&  /b/sanitizer-x86_64-linux-autoconf/build/tsan_debug_build/tools/clang/runtime/compiler-rt-bins/test/tsan/X86_64Config/Output/java_finalizer2.cpp.tmp 2>&1 | FileCheck /b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/test/tsan/java_finalizer2.cpp
--
Exit Code: 1

Command Output (stderr):
--
/b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/test/tsan/java_finalizer2.cpp:82:11: error: CHECK: expected string not found in input
// CHECK: DONE
          ^
<stdin>:1:1: note: scanning from here
FATAL: ThreadSanitizer CHECK failed: /b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/lib/tsan/rtl/tsan_sync.cpp:69 "((*meta)) == ((0))" (0x4000003e, 0x0)
^
<stdin>:5:12: note: possible intended match here
 rust-lang#3 __tsan::OnUserAlloc(__tsan::ThreadState*, unsigned long, unsigned long, unsigned long, bool) /b/sanitizer-x86_64-linux-autoconf/build/llvm-project/compiler-rt/lib/tsan/rtl/tsan_mman.cpp:225:16 (java_finalizer2.cpp.tmp+0x4af407)
           ^

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-autoconf/builds/51143/steps/test%20tsan%20in%20debug%20compiler-rt%20build/logs/stdio

Fix heap object overlap by offsetting java heap as other tests are doing.

Author: dvyukov

compiler-rt/test/tsan/java_finalizer2.cpp

@@ -47,7 +47,7 @@ void *Ballast(void *p) {
 }
 
 int main() {
-  Heap* heap = (Heap*)calloc(sizeof(Heap), 1);
+  Heap* heap = (Heap*)calloc(sizeof(Heap), 2) + 1;
   __tsan_java_init((jptr)heap, sizeof(*heap));
   __tsan_java_alloc((jptr)heap, sizeof(*heap));
   // Ballast threads merely make the bug a bit easier to trigger.