Pin color type when a cross-context image is constructed

Fixes issues with gray images that may be incorrectly re-interpreted as
alpha when re-wrapped. (https://github.com/flutter/flutter/issues/15600)

Change-Id: I4a78466073e14d212108d168eed0b2df1bc92ffe
Reviewed-on: https://skia-review.googlesource.com/116484
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: Greg Daniel <egdaniel@google.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/tests/ImageTest.cpp b/tests/ImageTest.cpp
index 726a06adc3..98c2f03c2e 100644
--- a/tests/ImageTest.cpp
+++ b/tests/ImageTest.cpp
@@ -1021,6 +1021,35 @@ DEF_GPUTEST(SkImage_MakeCrossContextFromPixmapRelease, reporter, options) {
     });
 }
 
+DEF_GPUTEST(SkImage_CrossContextGrayAlphaConfigs, reporter, options) {
+
+    for (SkColorType ct : { kGray_8_SkColorType, kAlpha_8_SkColorType }) {
+        SkAutoPixmapStorage pixmap;
+        pixmap.alloc(SkImageInfo::Make(4, 4, ct, kPremul_SkAlphaType));
+
+        for (int i = 0; i < GrContextFactory::kContextTypeCnt; ++i) {
+            GrContextFactory testFactory(options);
+            GrContextFactory::ContextType ctxType = static_cast<GrContextFactory::ContextType>(i);
+            ContextInfo ctxInfo = testFactory.getContextInfo(ctxType);
+            GrContext* ctx = ctxInfo.grContext();
+            if (!ctx || !ctx->caps()->crossContextTextureSupport()) {
+                continue;
+            }
+
+            sk_sp<SkImage> image = SkImage::MakeCrossContextFromPixmap(ctx, pixmap, false, nullptr);
+            REPORTER_ASSERT(reporter, image);
+
+            sk_sp<SkColorSpace> texColorSpace;
+            sk_sp<GrTextureProxy> proxy = as_IB(image)->asTextureProxyRef(
+                ctx, GrSamplerState::ClampNearest(), nullptr, &texColorSpace, nullptr);
+            REPORTER_ASSERT(reporter, proxy);
+
+            bool expectAlpha = kAlpha_8_SkColorType == ct;
+            REPORTER_ASSERT(reporter, expectAlpha == GrPixelConfigIsAlphaOnly(proxy->config()));
+        }
+    }
+}
+
 static uint32_t GetIdForBackendObject(GrContext* ctx, GrBackendObject object) {
     if (!object) {
         return 0;