[HWASAN] Modified __hwasan::Thread::unique_id_ to be u32 instead of u64.

This is needed for LSAN integration work. LSAN uses context to store thread_id << 32 + stack_id. In order to fit both we would need thread_id to be 32 bit.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D139060

GitOrigin-RevId: f7c71611370d3f5f240b080edfce51cd1e4995ce
diff --git a/lib/hwasan/hwasan_thread.h b/lib/hwasan/hwasan_thread.h
index 3db7c1a..296fa8f 100644
--- a/lib/hwasan/hwasan_thread.h
+++ b/lib/hwasan/hwasan_thread.h
@@ -61,7 +61,7 @@
   void DisableTagging() { tagging_disabled_++; }
   void EnableTagging() { tagging_disabled_--; }
 
-  u64 unique_id() const { return unique_id_; }
+  u32 unique_id() const { return unique_id_; }
   void Announce() {
     if (announced_) return;
     announced_ = true;
@@ -89,7 +89,7 @@
   HeapAllocationsRingBuffer *heap_allocations_;
   StackAllocationsRingBuffer *stack_allocations_;
 
-  u64 unique_id_;  // counting from zero.
+  u32 unique_id_;  // counting from zero.
 
   u32 tagging_disabled_;  // if non-zero, malloc uses zero tag in this thread.