add Make factory to SkMemoryStream (simplify call-sites)

Bug: skia:6888
Change-Id: Ia4e432673ed089a91229697c8dde0489f220000d
Reviewed-on: https://skia-review.googlesource.com/26884
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/src/codec/SkRawCodec.cpp b/src/codec/SkRawCodec.cpp
index dbcbd28..cf41d17 100644
--- a/src/codec/SkRawCodec.cpp
+++ b/src/codec/SkRawCodec.cpp
@@ -288,7 +288,7 @@
                 }
             }
         }
-        return skstd::make_unique<SkMemoryStream>(data);
+        return SkMemoryStream::Make(data);
     }
 
 private:
@@ -381,7 +381,7 @@
             sk_sp<SkData> data(SkData::MakeWithCopy(
                 static_cast<const uint8_t*>(fStream->getMemoryBase()) + offset, bytesToRead));
             fStream.reset();
-            return skstd::make_unique<SkMemoryStream>(data);
+            return SkMemoryStream::Make(data);
         } else {
             sk_sp<SkData> data(SkData::MakeUninitialized(bytesToRead));
             if (!fStream->seek(offset)) {
@@ -391,7 +391,7 @@
             if (bytesRead < bytesToRead) {
                 data = SkData::MakeSubset(data.get(), 0, bytesRead);
             }
-            return skstd::make_unique<SkMemoryStream>(data);
+            return SkMemoryStream::Make(data);
         }
     }
 private: