[tracing] Introduce MemoryDumpArgs to enable light and heavy dumps

gin/v8_isolate_memory_dump_provider_unittest.cc

Index: gin/v8_isolate_memory_dump_provider_unittest.cc
diff --git a/gin/v8_isolate_memory_dump_provider_unittest.cc b/gin/v8_isolate_memory_dump_provider_unittest.cc
index b1693cdf062fc7583f1bf4c3aa9227b7e2471e6a..3a0bfd3a5f3cb82a2f776743fe72eae9e1d4e324 100644
--- a/gin/v8_isolate_memory_dump_provider_unittest.cc
+++ b/gin/v8_isolate_memory_dump_provider_unittest.cc
@@ -24,6 +24,8 @@ TEST_F(V8MemoryDumpProviderTest, DumpStatistics) {
   scoped_ptr<base::trace_event::ProcessMemoryDump> process_memory_dump(
       new base::trace_event::ProcessMemoryDump(nullptr));
   instance_->isolate_memory_dump_provider_for_testing()->OnMemoryDump(
+      base::trace_event::MemoryDumpArgs(
+          base::trace_event::MemoryDumpArgs::LEVEL_OF_DETAIL_HIGH),
       process_memory_dump.get());
   const base::trace_event::ProcessMemoryDump::AllocatorDumpsMap&
       allocator_dumps = process_memory_dump->allocator_dumps();