DM: allow SKPs to be smaller than 1000x1000

dm/DMSrcSink.cpp

 #include "DMSrcSink.h"
 #include "SamplePipeControllers.h"
 #include "SkCommonFlags.h"
 #include "SkCodec.h"
 #include "SkDocument.h"
 #include "SkError.h"
 #include "SkMultiPictureDraw.h"
 #include "SkNullCanvas.h"
 #include "SkOSFile.h"
+#include "SkPictureData.h"
 #include "SkPictureRecorder.h"
 #include "SkRandom.h"
 #include "SkSVGCanvas.h"
 #include "SkStream.h"
 #include "SkXMLWriter.h"
 
 DEFINE_bool(codec, false, "Use SkCodec instead of SkImageDecoder");
 
 namespace DM {
 
@@ skipping 150 matching lines @@
     if (!pic) {
         return SkStringPrintf("Couldn't decode %s as a picture.", fPath.c_str());
     }
     stream.reset((SkStream*)NULL);  // Might as well drop this when we're done with it.
     canvas->clipRect(kSKPViewport);
     canvas->drawPicture(pic);
     return "";
 }
 
 SkISize SKPSrc::size() const {
-    // This may be unnecessarily large.
-    return kSKPViewport.roundOut().size();
+    SkAutoTDelete<SkStream> stream(SkStream::NewFromFile(fPath.c_str()));
+    if (!stream) {
+        return SkISize::Make(0,0);
+    }
+    SkPictInfo info;
+    if (!SkPicture::InternalOnly_StreamIsSKP(stream, &info)) {
+        return SkISize::Make(0,0);
+    }
+    SkRect viewport = kSKPViewport;
+    if (!viewport.intersect(info.fCullRect)) {
+        return SkISize::Make(0,0);
+    }
+    return viewport.roundOut().size();
 }
 
 Name SKPSrc::name() const { return SkOSPath::Basename(fPath.c_str()); }
 
 /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
 
 Error NullSink::draw(const Src& src, SkBitmap*, SkWStream*, SkString*) const {
     SkAutoTDelete<SkCanvas> canvas(SkCreateNullCanvas());
     return src.draw(canvas);
 }
@@ skipping 341 matching lines @@
             surfaces.unrefAll();
             return "";
         }
         SkISize size() const SK_OVERRIDE { return fSize; }
         Name name() const SK_OVERRIDE { sk_throw(); return ""; }  // No one should be calling this.
     } proxy(fW, fH, pic, src.size());
     return fSink->draw(proxy, bitmap, stream, log);
 }
 
 }  // namespace DM