Add configurable limit to allocations in heap profiler.

base/trace_event/trace_config.h

Index: base/trace_event/trace_config.h
diff --git a/base/trace_event/trace_config.h b/base/trace_event/trace_config.h
index 72ca5f868785691b7686fef576f6eb59218c4592..f8504479bf6730452fccd598cf6686a854ad8a40 100644
--- a/base/trace_event/trace_config.h
+++ b/base/trace_event/trace_config.h
@@ -40,14 +40,39 @@ class BASE_EXPORT TraceConfig {
  public:
   typedef std::vector<std::string> StringList;
 
-  // Specifies the memory dump config for tracing. Used only when
-  // "memory-infra" category is enabled.
+  // Specifies the triggers in the memory dump config.
   struct MemoryDumpTriggerConfig {

[Primiano Tucci (use gerrit), 2016/04/22 14:18:29]

I think just for the sake of legibility these structs (this and
HeapProfilerOptions) be inner structs of MemoryDumpConfig, so it's clear they
all belong to the same thing.

[Maria, 2016/04/25 18:37:24]

Done.

     uint32_t periodic_interval_ms;
     MemoryDumpLevelOfDetail level_of_detail;
   };
 
-  typedef std::vector<MemoryDumpTriggerConfig> MemoryDumpConfig;
+  // Specifies the configuration options for the heap profiler.
+  struct HeapProfilerOptions {
+    // Default value for |breakdown_threshold_bytes|.
+    enum { kDefaultBreakdownThresholdBytes = 1024 };
+
+    HeapProfilerOptions();
+    ~HeapProfilerOptions();
+
+    // Reset the options to default.
+    void Clear();
+
+    uint32_t breakdown_threshold_bytes;
+  };
+
+  // Specifies the memory dump config for tracing.
+  // Used only when "memory-infra" category is enabled.
+  struct MemoryDumpConfig {
+    MemoryDumpConfig();
+    MemoryDumpConfig(const MemoryDumpConfig& other);
+    ~MemoryDumpConfig();
+
+    // Reset the values in the config.
+    void Clear();
+
+    std::vector<MemoryDumpTriggerConfig> triggers;
+    HeapProfilerOptions heap_profiler_options;
+  };
 
   TraceConfig();
 
@@ -212,6 +237,8 @@ class BASE_EXPORT TraceConfig {
                          const StringList& categories) const;
 
   void SetMemoryDumpConfig(const base::DictionaryValue& memory_dump_config);
+  void SetTriggers(const base::DictionaryValue& memory_dump_config);

[Primiano Tucci (use gerrit), 2016/04/22 14:18:29]

why do we have these intermediate setters (SetTriggers and
SetHeapProfilerOptions)?
Can we have just the SetMemoryDUmpConfig?

[Maria, 2016/04/25 18:37:24]

I found it more clean to do it this way rather than nest the code inside checks,
but I don't care too much. Combined the methods.

+  void SetHeapProfilerOptions(const base::DictionaryValue& memory_dump_config);
   void SetDefaultMemoryDumpConfig();
 
   // Convert TraceConfig to the dict representation of the TraceConfig.