Enable strict gcstress unwind checks. am: 022f9e555b am: c02a438979 am: bc542839c6

Original change: https://android-review.googlesource.com/c/platform/art/+/1705474

Change-Id: Id2e5fa6816a835302f7218ebfbe1bf628396b192
diff --git a/runtime/backtrace_helper.cc b/runtime/backtrace_helper.cc
index 74e6130..994b0fa 100644
--- a/runtime/backtrace_helper.cc
+++ b/runtime/backtrace_helper.cc
@@ -46,7 +46,7 @@
 
 // Strict integrity check of the backtrace:
 // All methods must have a name, all the way to "main".
-static constexpr bool kStrictUnwindChecks = false;
+static constexpr bool kStrictUnwindChecks = true;
 
 struct UnwindHelper : public TLSData {
   static constexpr const char* kTlsKey = "UnwindHelper::kTlsKey";