expose api to count the number of ops in a picture

src/core/SkPicture.cpp

Index: src/core/SkPicture.cpp
diff --git a/src/core/SkPicture.cpp b/src/core/SkPicture.cpp
index fa4c103d5ce1ca5506a5fc7b7731b7bf9c24572a..ff9eb2789a845962c1f9929ecbf8f0a223dba179 100644
--- a/src/core/SkPicture.cpp
+++ b/src/core/SkPicture.cpp
@@ -173,6 +173,16 @@ SkPicture::AccelData::Domain SkPicture::AccelData::GenerateDomain() {
 
 ///////////////////////////////////////////////////////////////////////////////
 
+int SkPicture::countOps() const {
+    if (fRecord.get()) {
+        return fRecord->count();
+    } else if (fData.get()) {
+        return fData->countOps();
+    } else {
+        return 0;
+    }
+}
+
 uint32_t SkPicture::OperationList::offset(int index) const {
     SkASSERT(index < fOps.count());
     return ((SkPictureStateTree::Draw*)fOps[index])->fOffset;