Fix many return-std-move-in-c++11 warnings

Change-Id: Ib0042cf412fe3c5fa600b7ae644d16740457535e
Reviewed-on: https://skia-review.googlesource.com/121354
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Auto-Submit: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
diff --git a/src/pdf/SkPDFMetadata.cpp b/src/pdf/SkPDFMetadata.cpp
index d91272c..ccb3ef3 100644
--- a/src/pdf/SkPDFMetadata.cpp
+++ b/src/pdf/SkPDFMetadata.cpp
@@ -132,7 +132,7 @@
     if (metadata.fModified.fEnabled) {
         dict->insertString("ModDate", pdf_date(metadata.fModified.fDateTime));
     }
-    return dict;
+    return std::move(dict);
 }
 
 SkPDFMetadata::UUID SkPDFMetadata::CreateUUID(
@@ -184,7 +184,7 @@
             SkString(reinterpret_cast<const char*>(&doc), sizeof(UUID)));
     array->appendString(
             SkString(reinterpret_cast<const char*>(&instance), sizeof(UUID)));
-    return array;
+    return std::move(array);
 }
 
 // Convert a block of memory to hexadecimal.  Input and output pointers will be