[tracing] Turn StackFrame into struct.

base/trace_event/heap_profiler_allocation_register_unittest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/trace_event/heap_profiler_allocation_register.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include "base/process/process_metrics.h"
@@ skipping 89 matching lines @@
   reg.Remove(reinterpret_cast<void*>(4));  // Remove never inserted address.
 
   EXPECT_EQ(2u, OrAllAddresses(reg));
 }
 
 TEST_F(AllocationRegisterTest, DoubleInsertOverwrites) {
   // TODO(ruuda): Although double insert happens in practice, it should not.
   // Find out the cause and ban double insert if possible.
   AllocationRegister reg;
   AllocationContext ctx = AllocationContext::Empty();
-  StackFrame frame1 = "Foo";
-  StackFrame frame2 = "Bar";
+  StackFrame frame1 = StackFrame::FromTraceEventName("Foo");
+  StackFrame frame2 = StackFrame::FromTraceEventName("Bar");
+
+  ctx.backtrace.frame_count = 1;
 
   ctx.backtrace.frames[0] = frame1;
   reg.Insert(reinterpret_cast<void*>(1), 11, ctx);
 
   {
     AllocationRegister::Allocation elem = *reg.begin();
 
     EXPECT_EQ(frame1, elem.context.backtrace.frames[0]);
     EXPECT_EQ(11u, elem.size);
     EXPECT_EQ(reinterpret_cast<void*>(1), elem.address);
@@ skipping 158 matching lines @@
   const size_t cells_per_page = GetNumCellsPerPage();
 
   ASSERT_DEATH(for (size_t j = 0; j < cells_per_page; j++) {
     reg.Insert(reinterpret_cast<void*>(i + j), 1, ctx);
   }, "");
 }
 #endif
 
 }  // namespace trace_event
 }  // namespace base