[tracing] Adding task information to heap profiler

base/trace_event/heap_profiler_allocation_context_tracker.cc

Index: base/trace_event/heap_profiler_allocation_context_tracker.cc
diff --git a/base/trace_event/heap_profiler_allocation_context_tracker.cc b/base/trace_event/heap_profiler_allocation_context_tracker.cc
index 8a4dbc7d8ca8f22f698ed0de63c4b9a408dd57e1..f26465a2c71c7a586d0f28d667c3382d5b98b49e 100644
--- a/base/trace_event/heap_profiler_allocation_context_tracker.cc
+++ b/base/trace_event/heap_profiler_allocation_context_tracker.cc
@@ -32,9 +32,11 @@ void DestructAllocationContextTracker(void* alloc_ctx_tracker) {
 
 }  // namespace
 
-AllocationContextTracker::AllocationContextTracker() {
+AllocationContextTracker::AllocationContextTracker()
+    : current_task_file_name_(nullptr) {
   pseudo_stack_.reserve(kMaxStackDepth);
 }
+
 AllocationContextTracker::~AllocationContextTracker() {}
 
 // static
@@ -113,6 +115,24 @@ void AllocationContextTracker::PopPseudoStackFrame(StackFrame frame) {
 }
 
 // static
+void AllocationContextTracker::SetThreadName(const char* name) {
+  auto tracker = AllocationContextTracker::GetThreadLocalTracker();
+  CHECK(tracker);

[Primiano Tucci (use gerrit), 2016/03/15 16:44:33]

NO need for this CHECK. If tracker is nullptr, this will naturally die on the
next statement while trying to insert.

[ssid, 2016/03/17 00:11:47]

Done.

+
+  // The thread name is added as the first entry in the psuedo stack. This is
+  // not removed until the tls is destroyed when thread dies.
+  tracker->pseudo_stack_.insert(tracker->pseudo_stack_.begin(),
+                                static_cast<StackFrame>(name));
+}
+
+// static
+void AllocationContextTracker::SetCurrentTaskFileName(const char* file_name) {
+  AllocationContextTracker* tracker = GetThreadLocalTracker();
+  CHECK(tracker);
+  tracker->current_task_file_name_ = file_name;
+}
+
+// static
 AllocationContext AllocationContextTracker::GetContextSnapshot() {
   AllocationContextTracker* tracker = GetThreadLocalTracker();
   AllocationContext ctx;
@@ -133,7 +153,9 @@ AllocationContext AllocationContextTracker::GetContextSnapshot() {
     std::fill(dst, dst_end, nullptr);
   }
 
-  ctx.type_name = nullptr;
+  // Set the default type name to file name where the task was posted from.

[Primiano Tucci (use gerrit), 2016/03/15 16:44:33]

Can you add a TODO: this should be a 3rd dimension (component name) in the heap
profiler, not piggy back on the type.

[ssid, 2016/03/17 00:11:47]

Done.

+  // Trace viewer uses the file name to categorize allocation by file name.
+  ctx.type_name = tracker->current_task_file_name_;
 
   return ctx;
 }