Add support for light dumps in SkTraceMemoryDump interface.

include/core/SkTraceMemoryDump.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkTraceMemoryDump_DEFINED
 #define SkTraceMemoryDump_DEFINED
 
 #include "SkTypes.h"
 
 class SkDiscardableMemory;
 
 /**
  * Interface for memory tracing.
  * This interface is meant to be passed as argument to the memory dump methods of Skia objects.
  * The implementation of this interface is provided by the embedder.
  */
 class SK_API SkTraceMemoryDump {
 public:
     /**
+     * Enum to specify the level of the requested details for the dump from the Skia objects.
+     */
+    enum LevelOfDetail {
+        // Dump only the minimal details to get the total memory usage (Usually just the totals).
+        kLight_LevelOfDetail,
+
+        // Dump the detailed breakdown of the objects in the caches.
+        kObjectsBreakdowns_LevelOfDetail
+    };
+
+    /**
      *  Appends a new memory dump (i.e. a row) to the trace memory infrastructure.
      *  If dumpName does not exist yet, a new one is created. Otherwise, a new column is appended to
      *  the previously created dump.
      *  Arguments:
      *    dumpName: an absolute, slash-separated, name for the item being dumped
      *        e.g., "skia/CacheX/EntryY".
      *    valueName: a string indicating the name of the column.
      *        e.g., "size", "active_size", "number_of_objects".
      *        This string is supposed to be long lived and is NOT copied.
      *    units: a string indicating the units for the value.
@@ skipping 15 matching lines @@
                                   const char* backingType,
                                   const char* backingObjectId) = 0;
 
     /**
      * Specialization for memory backed by discardable memory.
      */
     virtual void setDiscardableMemoryBacking(
         const char* dumpName,
         const SkDiscardableMemory& discardableMemoryObject) = 0;
 
+    /**
+     * Returns the type of details requested in the dump. The granularity of the dump is supposed to
+     * match the LevelOfDetail argument. The level of detail must not affect the total size
+     * reported, but only granularity of the child entries.
+     */
+    virtual LevelOfDetail getRequestedDetails() const = 0;
+
 protected:
     virtual ~SkTraceMemoryDump() { }
 };
 
 #endif