Fix DCHECK failures from Class::VisitFieldRoots

We now use GetDeclaringClassUnchecked when marking roots to fix
flaky test failures. Fixed a race condition in root marking where
we could have non zero field array length with a null pointer.
Fixed a race condition where we could be marking roots before
FixupTemporaryDeclaringClass had finished. The solution is to
only do the declaring class CHECK if we are at least resolved.
Fixed JDWP tests by changing FieldId / MethodId to be 64 bits.

Also some cleanup.

Change-Id: Ibac09519860d93c3f68a5cc964bbc91dc10a279a

1 files changed, 3 insertions, 2 deletions

diff --git a/runtime/gc_root.h b/runtime/gc_root.h
index 0d3c93b83d..bdc7d5c8e6 100644
--- a/runtime/gc_root.h
+++ b/runtime/gc_root.h
@@ -50,7 +50,7 @@ enum RootType {
 };
 std::ostream& operator<<(std::ostream& os, const RootType& root_type);
 
-// Only used by hprof. tid and root_type are only used by hprof.
+// Only used by hprof. thread_id_ and type_ are only used by hprof.
 class RootInfo {
  public:
   // Thread id 0 is for non thread roots.
@@ -85,12 +85,13 @@ class RootVisitor {
  public:
   virtual ~RootVisitor() { }
 
-  // Single root versions, not overridable.
+  // Single root version, not overridable.
   ALWAYS_INLINE void VisitRoot(mirror::Object** roots, const RootInfo& info)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     VisitRoots(&roots, 1, info);
   }
 
+  // Single root version, not overridable.
   ALWAYS_INLINE void VisitRootIfNonNull(mirror::Object** roots, const RootInfo& info)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     if (*roots != nullptr) {