[tracing] Introduce MemoryDumpArgs to enable light and heavy dumps

base/trace_event/process_memory_totals_dump_provider_unittest.cc

Index: base/trace_event/process_memory_totals_dump_provider_unittest.cc
diff --git a/base/trace_event/process_memory_totals_dump_provider_unittest.cc b/base/trace_event/process_memory_totals_dump_provider_unittest.cc
index f9bb6c071ce08552957ffb0d5b2c5e64990deb13..14aa8df6e29c29032421d3e2741cb55d9250fc07 100644
--- a/base/trace_event/process_memory_totals_dump_provider_unittest.cc
+++ b/base/trace_event/process_memory_totals_dump_provider_unittest.cc
@@ -12,18 +12,19 @@ namespace base {
 namespace trace_event {
 
 TEST(ProcessMemoryTotalsDumpProviderTest, DumpRSS) {
+  const MemoryDumpArgs high_detail_args(MemoryDumpArgs::LEVEL_OF_DETAIL_HIGH);
   auto pmtdp = ProcessMemoryTotalsDumpProvider::GetInstance();
   scoped_ptr<ProcessMemoryDump> pmd_before(new ProcessMemoryDump(nullptr));
   scoped_ptr<ProcessMemoryDump> pmd_after(new ProcessMemoryDump(nullptr));
 
   ProcessMemoryTotalsDumpProvider::rss_bytes_for_testing = 1024;
-  pmtdp->OnMemoryDump(pmd_before.get());
+  pmtdp->OnMemoryDump(high_detail_args, pmd_before.get());
 
   // Pretend that the RSS of the process increased of +1M.
   const size_t kAllocSize = 1048576;
   ProcessMemoryTotalsDumpProvider::rss_bytes_for_testing += kAllocSize;
 
-  pmtdp->OnMemoryDump(pmd_after.get());
+  pmtdp->OnMemoryDump(high_detail_args, pmd_after.get());
 
   ProcessMemoryTotalsDumpProvider::rss_bytes_for_testing = 0;