MultiPictureDraw is taskgroup aware.

tests/LazyPtrTest.cpp

 #include "Test.h"
 #include "SkLazyPtr.h"
+#include "SkRunnable.h"
 #include "SkTaskGroup.h"
 
 namespace {
 
 struct CreateIntFromFloat {
     CreateIntFromFloat(float val) : fVal(val) {}
     int* operator()() const { return SkNEW_ARGS(int, ((int)fVal)); }
     float fVal;
 };
 
@@ skipping 57 matching lines @@
     for (int i = 0; i < kRacers; i++) {
         tg.add(racers + i);
     }
     tg.wait();
 
     for (int i = 1; i < kRacers; i++) {
         REPORTER_ASSERT(r, racers[i].fSeen);
         REPORTER_ASSERT(r, racers[i].fSeen == racers[0].fSeen);
     }
 }