[standalone] Remove kAsanDefaultOptions.

The test harness sets options via ASAN_OPTIONS. This makes our treatment of ASAN consistent with the other sanitizers.

Also fix a leak through RetainedReasonsWriter that this unmasked.

TEST=ci
Change-Id: I96cc6018b4859977d2bb7290b8822c91d99705cb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/394665
Reviewed-by: Alexander Aprelev <[email protected]>
Commit-Queue: Ryan Macnak <[email protected]>

Author: rmacnak-google

runtime/bin/BUILD.gn

@@ -215,7 +215,6 @@ template("build_gen_snapshot") {
     defines = [ "EXCLUDE_CFE_AND_KERNEL_PLATFORM" ]
 
     sources = [
-      "address_sanitizer.cc",
       "builtin.cc",
       "builtin.h",
       "error_exit.cc",

runtime/bin/address_sanitizer.cc

@@ -176,10 +176,12 @@ struct RetainReasons : public AllStatic {
       "signature of entry point function";
 };
 
-class RetainedReasonsWriter : public ValueObject {
+class RetainedReasonsWriter : public StackResource {
  public:
   explicit RetainedReasonsWriter(Zone* zone)
-      : zone_(zone), retained_reasons_map_(zone) {}
+      : StackResource(Thread::Current()),
+        zone_(zone),
+        retained_reasons_map_(zone) {}
 
   bool Init(const char* filename) {
     if (filename == nullptr) return false;