[Sanitizer] Change InitializeFlags() signatures. NFC.

These functions are always used to initialize singleton flags(), as
well as other global data (common_flags()).

llvm-svn: 228894
diff --git a/compiler-rt/lib/tsan/dd/dd_rtl.cc b/compiler-rt/lib/tsan/dd/dd_rtl.cc
index 2ba1ee3..99b8ee5 100644
--- a/compiler-rt/lib/tsan/dd/dd_rtl.cc
+++ b/compiler-rt/lib/tsan/dd/dd_rtl.cc
@@ -65,8 +65,8 @@
   return CurrentStackTrace(thr, 3);
 }
 
-void InitializeFlags(Flags *f, const char *env) {
-  internal_memset(f, 0, sizeof(*f));
+static void InitializeFlags() {
+  Flags *f = flags();
 
   // Default values.
   f->second_deadlock_stack = false;
@@ -84,7 +84,7 @@
   FlagParser parser;
   RegisterFlag(&parser, "second_deadlock_stack", "", &f->second_deadlock_stack);
   RegisterCommonFlags(&parser);
-  parser.ParseString(env);
+  parser.ParseString(GetEnv("DSAN_OPTIONS"));
   SetVerbosity(common_flags()->verbosity);
 }
 
@@ -93,7 +93,7 @@
   ctx = new(ctx_mem) Context();
 
   InitializeInterceptors();
-  InitializeFlags(flags(), GetEnv("DSAN_OPTIONS"));
+  InitializeFlags();
   ctx->dd = DDetector::Create(flags());
 }