Silence warning after f5e315ccf1a.

tools/PictureRenderer.cpp

Index: tools/PictureRenderer.cpp
diff --git a/tools/PictureRenderer.cpp b/tools/PictureRenderer.cpp
index f62a05d846df9a2dd3882e81090d2e7ad5064d43..9cb43f73d4c413bfdadc1129854a6c3c67da60fb 100644
--- a/tools/PictureRenderer.cpp
+++ b/tools/PictureRenderer.cpp
@@ -347,10 +347,10 @@ static bool write(SkCanvas* canvas, const SkString& outputDir, const SkString& i
     // we could combine results of different config types without conflicting filenames.
 
     if (NULL != jsonSummaryPtr) {
-        if (!generatedHash) {
-            SkAssertResult(SkBitmapHasher::ComputeDigest(bitmap, &hash));
-            generatedHash = true;
-        }
+        SkASSERT(!generatedHash);
+        SkAssertResult(SkBitmapHasher::ComputeDigest(bitmap, &hash));
+        generatedHash = true;
+
         jsonSummaryPtr->add(outputFilename.c_str(), hash);
     }