remove code from SK_SUPPORT_LEGACY_NEWFROMGENERATOR, eliminates caller of deprecated SkInstallDisca…

src/image/SkImage_Raster.cpp

Index: src/image/SkImage_Raster.cpp
diff --git a/src/image/SkImage_Raster.cpp b/src/image/SkImage_Raster.cpp
index 7eff9ef0f696d80fa016f4bc484f5c38bb049a88..042107e3e3fcb5ad51eb13d17c84e78e85d61cce 100644
--- a/src/image/SkImage_Raster.cpp
+++ b/src/image/SkImage_Raster.cpp
@@ -280,16 +280,3 @@ bool SkImage_Raster::onAsLegacyBitmap(SkBitmap* bitmap, LegacyBitmapMode mode) c
     }
     return this->INHERITED::onAsLegacyBitmap(bitmap, mode);
 }
-
-#ifdef SK_SUPPORT_LEGACY_NEWFROMGENERATOR
-SkImage* SkImage::NewFromGenerator(SkImageGenerator* generator, const SkIRect* subset) {
-    SkBitmap bitmap;
-    if (!SkInstallDiscardablePixelRef(generator, subset, &bitmap, nullptr)) {
-        return nullptr;
-    }
-    if (0 == bitmap.width() || 0 == bitmap.height()) {
-        return nullptr;
-    }
-    return new SkImage_Raster(bitmap, nullptr);
-}
-#endif