[tracing] Switch to new heap dump format.

base/BUILD.gn

Index: base/BUILD.gn
diff --git a/base/BUILD.gn b/base/BUILD.gn
index 19fe0bc0f6ce6fb0e1ada1fd0c47228819c9817c..d9b1a76fba9232c9e05012865ff43b40a65925a1 100644
--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -955,12 +955,14 @@ component("base") {
     "trace_event/heap_profiler_allocation_register_win.cc",
     "trace_event/heap_profiler_event_filter.cc",
     "trace_event/heap_profiler_event_filter.h",
-    "trace_event/heap_profiler_heap_dump_writer.cc",
-    "trace_event/heap_profiler_heap_dump_writer.h",
+    "trace_event/heap_profiler_event_writer.cc",
+    "trace_event/heap_profiler_event_writer.h",
     "trace_event/heap_profiler_serialization_state.cc",
     "trace_event/heap_profiler_serialization_state.h",
     "trace_event/heap_profiler_stack_frame_deduplicator.cc",
     "trace_event/heap_profiler_stack_frame_deduplicator.h",
+    "trace_event/heap_profiler_string_deduplicator.cc",
+    "trace_event/heap_profiler_string_deduplicator.h",
     "trace_event/heap_profiler_type_name_deduplicator.cc",
     "trace_event/heap_profiler_type_name_deduplicator.h",
     "trace_event/java_heap_dump_provider_android.cc",
@@ -2218,8 +2220,9 @@ test("base_unittests") {
     "trace_event/event_name_filter_unittest.cc",
     "trace_event/heap_profiler_allocation_context_tracker_unittest.cc",
     "trace_event/heap_profiler_allocation_register_unittest.cc",
-    "trace_event/heap_profiler_heap_dump_writer_unittest.cc",
+    "trace_event/heap_profiler_event_writer_unittest.cc",
     "trace_event/heap_profiler_stack_frame_deduplicator_unittest.cc",
+    "trace_event/heap_profiler_string_deduplicator_unittest.cc",
     "trace_event/heap_profiler_type_name_deduplicator_unittest.cc",
     "trace_event/java_heap_dump_provider_android_unittest.cc",
     "trace_event/memory_allocator_dump_unittest.cc",