Update from https://crrev.com/320343

tools/valgrind/asan/third_party/asan_symbolize.py

Index: tools/valgrind/asan/third_party/asan_symbolize.py
diff --git a/tools/valgrind/asan/third_party/asan_symbolize.py b/tools/valgrind/asan/third_party/asan_symbolize.py
index 59fceaaed814c031fc08ea301f146cfe862a3e8a..b9d3ad3ad2fe6b7b9c3b96d9b366149387d16291 100755
--- a/tools/valgrind/asan/third_party/asan_symbolize.py
+++ b/tools/valgrind/asan/third_party/asan_symbolize.py
@@ -23,6 +23,7 @@ sysroot_path = None
 binary_name_filter = None
 fix_filename_patterns = None
 logfile = sys.stdin
+allow_system_symbolizer = True
 
 # FIXME: merge the code that calls fix_filename().
 def fix_filename(file_name):
@@ -392,6 +393,8 @@ class SymbolizationLoop(object):
           [BreakpadSymbolizerFactory(binary), self.llvm_symbolizers[binary]])
     result = symbolizers[binary].symbolize(addr, binary, offset)
     if result is None:
+      if not allow_system_symbolizer:
+        raise Exception('Failed to launch or use llvm-symbolizer.')
       # Initialize system symbolizer only if other symbolizers failed.
       symbolizers[binary].append_symbolizer(
           SystemSymbolizerFactory(self.system, addr, binary))