Try switching cc::Picture to SkRTree.
Try switching cc::Picture to SkRTree.

Skia's been testing this on pictures from Chrome with promising results:
  - Never seen a correctness problem.
  - Building an SkRTree is always faster than an SkTileGrid,
    sometimes much faster.
  - While SkTileGrid serves exact tile queries a little faster,
    SkRTree is faster than SkTileGrid for non-exact queries.
  - We notice Chrome regularly makes non-exact queries hitting 2-4 tiles.

So we think this is probably at least a record-speed win, and there's a
reasonable chance it improves playback a little too.

Is there any better way to answer these performance questions other than
landing and seeing what chromeperf turns up?

BUG=skia:3085

Review URL: https://codereview.chromium.org/727413002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#304634}

Just-D/chromium-1,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,dushu1203/chromium.src,Fireblend/chromium-crosswalk,M4sse/chromium.src,Just-D/chromium-1,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,fujunwei/chromium-crosswalk,axinging/chromium-crosswalk,Chilledheart/chromium,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,M4sse/chromium.src,dushu1203/chromium.src,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,dushu1203/chromium.src,Pluto-tv/chromium-crosswalk,jaruba/chromium.src,Jonekee/chromium.src,krieger-od/nwjs_chromium.src,Fireblend/chromium-crosswalk,jaruba/chromium.src,dednal/chromium.src,markYoungH/chromium.src,Jonekee/chromium.src,krieger-od/nwjs_chromium.src,hgl888/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,M4sse/chromium.src,ltilve/chromium,Chilledheart/chromium,fujunwei/chromium-crosswalk,Just-D/chromium-1,PeterWangIntel/chromium-crosswalk,markYoungH/chromium.src,Pluto-tv/chromium-crosswalk,dushu1203/chromium.src,Chilledheart/chromium,Just-D/chromium-1,Chilledheart/chromium,Jonekee/chromium.src,Pluto-tv/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Fireblend/chromium-crosswalk,markYoungH/chromium.src,dednal/chromium.src,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,Just-D/chromium-1,fujunwei/chromium-crosswalk,Pluto-tv/chromium-crosswalk,jaruba/chromium.src,krieger-od/nwjs_chromium.src,markYoungH/chromium.src,M4sse/chromium.src,Jonekee/chromium.src,Jonekee/chromium.src,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,ltilve/chromium,dushu1203/chromium.src,krieger-od/nwjs_chromium.src,TheTypoMaster/chromium-crosswalk,hgl888/chromium-crosswalk,ltilve/chromium,jaruba/chromium.src,fujunwei/chromium-crosswalk,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk,dednal/chromium.src,axinging/chromium-crosswalk,dednal/chromium.src,chuan9/chromium-crosswalk,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,M4sse/chromium.src,chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,jaruba/chromium.src,axinging/chromium-crosswalk,ltilve/chromium,fujunwei/chromium-crosswalk,Fireblend/chromium-crosswalk,krieger-od/nwjs_chromium.src,markYoungH/chromium.src,Jonekee/chromium.src,ltilve/chromium,dushu1203/chromium.src,TheTypoMaster/chromium-crosswalk,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,M4sse/chromium.src,hgl888/chromium-crosswalk,dushu1203/chromium.src,Just-D/chromium-1,mohamed--abdel-maksoud/chromium.src,ltilve/chromium,mohamed--abdel-maksoud/chromium.src,TheTypoMaster/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,mohamed--abdel-maksoud/chromium.src,markYoungH/chromium.src,ltilve/chromium,Fireblend/chromium-crosswalk,M4sse/chromium.src,Chilledheart/chromium,axinging/chromium-crosswalk,Fireblend/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,Jonekee/chromium.src,axinging/chromium-crosswalk,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,jaruba/chromium.src,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,fujunwei/chromium-crosswalk,markYoungH/chromium.src,dednal/chromium.src,jaruba/chromium.src,fujunwei/chromium-crosswalk,krieger-od/nwjs_chromium.src,krieger-od/nwjs_chromium.src,markYoungH/chromium.src,dushu1203/chromium.src,M4sse/chromium.src,dednal/chromium.src,Chilledheart/chromium,krieger-od/nwjs_chromium.src,M4sse/chromium.src,PeterWangIntel/chromium-crosswalk,jaruba/chromium.src,Just-D/chromium-1,Chilledheart/chromium,Jonekee/chromium.src,M4sse/chromium.src,Fireblend/chromium-crosswalk,dednal/chromium.src,dushu1203/chromium.src,Fireblend/chromium-crosswalk,chuan9/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,ltilve/chromium,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,krieger-od/nwjs_chromium.src,Chilledheart/chromium,jaruba/chromium.src,krieger-od/nwjs_chromium.src,Pluto-tv/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,dednal/chromium.src,PeterWangIntel/chromium-crosswalk,Just-D/chromium-1,hgl888/chromium-crosswalk,Jonekee/chromium.src,Jonekee/chromium.src,axinging/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,Jonekee/chromium.src,markYoungH/chromium.src,fujunwei/chromium-crosswalk,dushu1203/chromium.src,dushu1203/chromium.src,jaruba/chromium.src,jaruba/chromium.src,fujunwei/chromium-crosswalk,markYoungH/chromium.src,TheTypoMaster/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,hgl888/chromium-crosswalk,Chilledheart/chromium,M4sse/chromium.src,dednal/chromium.src,TheTypoMaster/chromium-crosswalk,dednal/chromium.src,ltilve/chromium,dednal/chromium.src,PeterWangIntel/chromium-crosswalk,krieger-od/nwjs_chromium.src,mohamed--abdel-maksoud/chromium.src,mohamed--abdel-maksoud/chromium.src