Updates for improved PMA 'object' interface.

base/debug/activity_tracker.h

Index: base/debug/activity_tracker.h
diff --git a/base/debug/activity_tracker.h b/base/debug/activity_tracker.h
index 9ffcfaa844ba22ee9edee16dcade2481f5a4f011..114e2daeda65f633cd550d6d224610a148dbd14d 100644
--- a/base/debug/activity_tracker.h
+++ b/base/debug/activity_tracker.h
@@ -61,6 +61,11 @@ enum : int {
 // sized types to ensure no interoperability problems between 32-bit and
 // 64-bit systems.
 union ActivityData {
+  // SHA1(base::debug::ActivityData): Increment this if structure changes!
+  static constexpr uint32_t kPersistentTypeId = 0x72DC176D + 1;
+  // Expected size for 32/64-bit check. Update this if structure changes!
+  static constexpr size_t kExpectedInstanceSize = 8;

[manzagop (departed), 2017/02/17 15:50:55]

static_assert for this? Same below.

[bcwhite, 2017/02/17 15:52:11]

These sizes are asserted by the PMA when using the object interface.

+
   // Generic activities don't have any defined structure.
   struct {
     uint32_t id;   // An arbitrary identifier used for association.
@@ -162,7 +167,7 @@ class BASE_EXPORT ActivityTrackerMemoryAllocator {
   // Helper function to access an object allocated using this instance.
   template <typename T>
   T* GetAsObject(Reference ref) {
-    return allocator_->GetAsObject<T>(ref, object_type_);
+    return allocator_->GetAsObject<T>(ref);
   }
 
   // Similar to GetAsObject() but converts references to arrays of objects.
@@ -198,6 +203,12 @@ class BASE_EXPORT ActivityTrackerMemoryAllocator {
 // the |data| field. All fields must be explicitly sized types to ensure no
 // interoperability problems between 32-bit and 64-bit systems.
 struct Activity {
+  // SHA1(base::debug::Activity): Increment this if structure changes!
+  static constexpr uint32_t kPersistentTypeId = 0x99425159 + 1;
+  // Expected size for 32/64-bit check. Update this if structure changes!
+  static constexpr size_t kExpectedInstanceSize =
+      48 + ActivityData::kExpectedInstanceSize;
+
   // The type of an activity on the stack. Activities are broken into
   // categories with the category ID taking the top 4 bits and the lower
   // bits representing an action within that category. This combination