Set process phases in the StackSamplingProfiler.

components/metrics/call_stack_profile_metrics_provider.cc

Index: components/metrics/call_stack_profile_metrics_provider.cc
diff --git a/components/metrics/call_stack_profile_metrics_provider.cc b/components/metrics/call_stack_profile_metrics_provider.cc
index 77b27e0ba9689113b9773970fde963cf39153cd9..9bd823b34e917b1793907a8f3fd118a5ef1c842e 100644
--- a/components/metrics/call_stack_profile_metrics_provider.cc
+++ b/components/metrics/call_stack_profile_metrics_provider.cc
@@ -33,13 +33,14 @@ namespace metrics {
 
 namespace {
 
-// Provide a mapping from the C++ "enum" definition of various process phases
-// to the equivalent protobuf "enum" definition. This table-lookup conversion
-// allows for the implementation to evolve and still be compatible with the
-// protobuf -- even if there are ever more than 32 defined proto values, though
-// never more than 32 could be in-use in a given C++ version of the code.
+// Provide a mapping from the C++ "enum" definition of various process mile-
+// stones to the equivalent protobuf "enum" definition. This table-lookup
+// conversion allows for the implementation to evolve and still be compatible
+// with the protobuf -- even if there are ever more than 32 defined proto
+// values, though never more than 32 could be in-use in a given C++ version
+// of the code.
 const ProcessPhase
-    kProtoPhases[CallStackProfileMetricsProvider::PHASES_MAX_VALUE] = {
+    kProtoPhases[CallStackProfileMetricsProvider::MILESTONES_MAX_VALUE] = {
         ProcessPhase::MAIN_LOOP_START,
         ProcessPhase::MAIN_NAVIGATION_START,
         ProcessPhase::MAIN_NAVIGATION_FINISHED,
@@ -259,17 +260,18 @@ void CopySampleToProto(
 // protobuf uses a repeated field of individual values. Conversion tables
 // allow for arbitrary mapping, though no more than 32 in any given version
 // of the code.
-void CopyAnnotationsToProto(uint32_t new_phases,
+void CopyAnnotationsToProto(uint32_t new_milestones,
                             CallStackProfile::Sample* sample_proto) {
-  for (size_t bit = 0; new_phases != 0 && bit < sizeof(new_phases) * 8; ++bit) {
+  for (size_t bit = 0; new_milestones != 0 && bit < sizeof(new_milestones) * 8;
+       ++bit) {
     const uint32_t flag = 1U << bit;
-    if (new_phases & flag) {
+    if (new_milestones & flag) {
       if (bit >= arraysize(kProtoPhases)) {
         NOTREACHED();
         continue;
       }
       sample_proto->add_process_phase(kProtoPhases[bit]);
-      new_phases ^= flag;  // Bit is set so XOR will clear it.
+      new_milestones ^= flag;  // Bit is set so XOR will clear it.
     }
   }
 }
@@ -285,7 +287,7 @@ void CopyProfileToProto(
   if (ordering_spec == CallStackProfileParams::PRESERVE_ORDER) {
     // Collapse only consecutive repeated samples together.
     CallStackProfile::Sample* current_sample_proto = nullptr;
-    uint32_t phases = 0;
+    uint32_t milestones = 0;
     for (auto it = profile.samples.begin(); it != profile.samples.end(); ++it) {
       // Check if the sample is different than the previous one. Samples match
       // if the frame and all annotations are the same.
@@ -293,9 +295,9 @@ void CopyProfileToProto(
         current_sample_proto = proto_profile->add_sample();
         CopySampleToProto(*it, profile.modules, current_sample_proto);
         current_sample_proto->set_count(1);
-        CopyAnnotationsToProto(it->process_phases & ~phases,
+        CopyAnnotationsToProto(it->process_milestones & ~milestones,
                                current_sample_proto);
-        phases = it->process_phases;
+        milestones = it->process_milestones;
       } else {
         current_sample_proto->set_count(current_sample_proto->count() + 1);
       }
@@ -303,7 +305,7 @@ void CopyProfileToProto(
   } else {
     // Collapse all repeated samples together.
     std::map<StackSamplingProfiler::Sample, int> sample_index;
-    uint32_t phases = 0;
+    uint32_t milestones = 0;
     for (auto it = profile.samples.begin(); it != profile.samples.end(); ++it) {
       // Check for a sample already seen. Samples match if the frame and all
       // annotations are the same.
@@ -312,11 +314,12 @@ void CopyProfileToProto(
         CallStackProfile::Sample* sample_proto = proto_profile->add_sample();
         CopySampleToProto(*it, profile.modules, sample_proto);
         sample_proto->set_count(1);
-        CopyAnnotationsToProto(it->process_phases & ~phases, sample_proto);
+        CopyAnnotationsToProto(it->process_milestones & ~milestones,
+                               sample_proto);
         sample_index.insert(
             std::make_pair(
                 *it, static_cast<int>(proto_profile->sample().size()) - 1));
-        phases = it->process_phases;
+        milestones = it->process_milestones;
       } else {
         CallStackProfile::Sample* sample_proto =
             proto_profile->mutable_sample()->Mutable(location->second);