Exit before reaching some Nonfatal errors

dm/DM.cpp

Index: dm/DM.cpp
diff --git a/dm/DM.cpp b/dm/DM.cpp
index d35787e1c75d4a6492b7b5d16080e97d67fc6283..c8464599e5cf5f426be6c6d320962144ca415df0 100644
--- a/dm/DM.cpp
+++ b/dm/DM.cpp
@@ -463,18 +463,7 @@ static void push_image_gen_src(Path path, ImageGenSrc::Mode mode, SkAlphaType al
     push_src("image", folder, src);
 }
 
-static void push_codec_srcs(Path path) {
-    SkAutoTUnref<SkData> encoded(SkData::NewFromFileName(path.c_str()));
-    if (!encoded) {
-        info("Couldn't read %s.", path.c_str());
-        return;
-    }
-    SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(encoded));
-    if (nullptr == codec.get()) {
-        info("Couldn't create codec for %s.", path.c_str());
-        return;
-    }
-
+static void push_codec_srcs(Path path, SkCodec* codec) {
     // native scaling is only supported by WEBP and JPEG
     bool supportsNativeScaling = false;
 
@@ -641,7 +630,7 @@ static void push_brd_src(Path path, CodecSrc::DstColorType dstColorType, BRDSrc:
     push_src("image", folder, src);
 }
 
-static void push_brd_srcs(Path path) {
+static void push_brd_srcs(Path path, SkCodec* codec) {
     // Only run Index8 and grayscale to one sampleSize and Mode. Though interesting
     // to test these color types, they should not reveal anything across various
     // sampleSizes and Modes
@@ -664,7 +653,14 @@ static void push_brd_srcs(Path path) {
             BRDSrc::kDivisor_Mode,
     };
 
+    const int width = codec->getInfo().width();
+    const int height = codec->getInfo().height();
     for (uint32_t sampleSize : sampleSizes) {
+        if ((width / sampleSize <= 10 || height / sampleSize <= 10) && 1 != sampleSize) {
+            // Scaling very small images is uninteresting. After the first iteration,
+            // the image will only get smaller, so break here.
+            break;
+        }
         for (BRDSrc::Mode mode : modes) {
             push_brd_src(path, CodecSrc::kGetFromCanvas_DstColorType, mode, sampleSize);
         }
@@ -707,14 +703,25 @@ static bool gather_srcs() {
     }
 
     for (auto image : images) {
-        push_codec_srcs(image);
+        SkAutoTUnref<SkData> encoded(SkData::NewFromFileName(image.c_str()));
+        if (!encoded) {
+            info("Couldn't read %s.", image.c_str());
+            continue;
+        }
+        SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(encoded));
+        if (nullptr == codec.get()) {
+            info("Couldn't create codec for %s.", image.c_str());
+            continue;
+        }
+
+        push_codec_srcs(image, codec);
         if (FLAGS_simpleCodec) {
             continue;
         }
 
         const char* ext = strrchr(image.c_str(), '.');
         if (ext && brd_supported(ext+1)) {
-            push_brd_srcs(image);
+            push_brd_srcs(image, codec);
         }
     }