Revert "Disable bitstring tests."

This reverts commit 2c5b48da62da3259a17cf9fab260e2e7f91c8d27.

Reason for revert: b/148125232 was fixed
Bug: 148125232

Change-Id: I36ba22ffe018503f5556e47646703ff0cd35b68f
diff --git a/runtime/subtype_check_test.cc b/runtime/subtype_check_test.cc
index 81eb7bb..719e5d9 100644
--- a/runtime/subtype_check_test.cc
+++ b/runtime/subtype_check_test.cc
@@ -24,9 +24,6 @@
 constexpr size_t BitString::kBitSizeAtPosition[BitString::kCapacity];
 constexpr size_t BitString::kCapacity;
 
-// Disable due to b/148125232
-#define DISABLED_TEST_F(a, b) TEST_F(a, DISABLED_##b)
-
 struct MockClass {
   explicit MockClass(MockClass* parent, size_t x = 0, size_t y = 0) {
     parent_ = parent;
@@ -341,7 +338,7 @@
   std::vector<std::unique_ptr<MockClass>> all_classes_;
 };
 
-DISABLED_TEST_F(SubtypeCheckTest, LookupAllChildren) {
+TEST_F(SubtypeCheckTest, LookupAllChildren) {
   MockScopedLockSubtypeCheck lock_a;
   MockScopedLockMutator lock_b;
   using SCTree = MockSubtypeCheck;
@@ -355,7 +352,7 @@
   });
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, LookupRoot) {
+TEST_F(SubtypeCheckTest, LookupRoot) {
   MockScopedLockSubtypeCheck lock_a;
   MockScopedLockMutator lock_b;
   using SCTree = MockSubtypeCheck;
@@ -365,7 +362,7 @@
   EXPECT_EQ(SubtypeCheckInfo::kSubtypeOf, root.IsSubtypeOf(root)) << root;
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitializedFirstLevel) {
+TEST_F(SubtypeCheckTest, EnsureInitializedFirstLevel) {
   MockScopedLockSubtypeCheck lock_a;
   MockScopedLockMutator lock_b;
   using SCTree = MockSubtypeCheck;
@@ -390,7 +387,7 @@
   }
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureAssignedFirstLevel) {
+TEST_F(SubtypeCheckTest, EnsureAssignedFirstLevel) {
   MockScopedLockSubtypeCheck lock_a;
   MockScopedLockMutator lock_b;
   using SCTree = MockSubtypeCheck;
@@ -415,7 +412,7 @@
   }
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitializedSecondLevelWithPreassign) {
+TEST_F(SubtypeCheckTest, EnsureInitializedSecondLevelWithPreassign) {
   MockScopedLockSubtypeCheck lock_a;
   MockScopedLockMutator lock_b;
   using SCTree = MockSubtypeCheck;
@@ -465,7 +462,7 @@
   }
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitializedSecondLevelDontPreassign) {
+TEST_F(SubtypeCheckTest, EnsureInitializedSecondLevelDontPreassign) {
   MockScopedLockSubtypeCheck lock_a;
   MockScopedLockMutator lock_b;
   using SCTree = MockSubtypeCheck;
@@ -687,7 +684,7 @@
   EnsureStateChangedTestRecursive(root, /*cur_depth=*/0u, depth, transitions);
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitialized_NoOverflow) {
+TEST_F(SubtypeCheckTest, EnsureInitialized_NoOverflow) {
   auto transitions = [](MockClass* kls) {
     UNUSED(kls);
     return MockSubtypeOfTransition::kInitialized;
@@ -759,7 +756,7 @@
                                          expected_uninitialize);
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureAssigned_TooDeep) {
+TEST_F(SubtypeCheckTest, EnsureAssigned_TooDeep) {
   auto transitions = [](MockClass* kls) {
     UNUSED(kls);
     return MockSubtypeOfTransition::kAssigned;
@@ -783,7 +780,7 @@
   EnsureStateChangedTestRecursiveGeneric(root_, 0u, kMaxDepthForThisTest, transitions, expected);
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureAssigned_TooDeep_OfTooDeep) {
+TEST_F(SubtypeCheckTest, EnsureAssigned_TooDeep_OfTooDeep) {
   auto transitions = [](MockClass* kls) {
     UNUSED(kls);
     return MockSubtypeOfTransition::kAssigned;
@@ -844,7 +841,7 @@
   return false;
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitialized_TooWide) {
+TEST_F(SubtypeCheckTest, EnsureInitialized_TooWide) {
   auto transitions = [](MockClass* kls) {
     UNUSED(kls);
     return MockSubtypeOfTransition::kAssigned;
@@ -888,7 +885,7 @@
                                          expected);
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitialized_TooWide_TooWide) {
+TEST_F(SubtypeCheckTest, EnsureInitialized_TooWide_TooWide) {
   auto transitions = [](MockClass* kls) {
     UNUSED(kls);
     return MockSubtypeOfTransition::kAssigned;
@@ -1008,7 +1005,7 @@
   ASSERT_NO_FATAL_FAILURE(kls_root->Visit(visit_func));
 }
 
-DISABLED_TEST_F(SubtypeCheckTest, EnsureInitialized_TooWide_TooDeep) {
+TEST_F(SubtypeCheckTest, EnsureInitialized_TooWide_TooDeep) {
   auto transitions = [](MockClass* kls) {
     UNUSED(kls);
     return MockSubtypeOfTransition::kAssigned;