Use mixed samples in GrDynamicAtlas

Change-Id: I0871f2e87be857ebf8577b212b318054a2ad84dd
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/269908
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>

Author: csmartdalton86

src/gpu/GrDynamicAtlas.cpp

@@ -50,8 +50,11 @@ sk_sp<GrTextureProxy> GrDynamicAtlas::MakeLazyAtlasProxy(
         InternalMultisample internalMultisample, const GrCaps& caps,
         GrSurfaceProxy::UseAllocator useAllocator) {
     GrBackendFormat format = caps.getDefaultBackendFormat(colorType, GrRenderable::kYes);
-    int sampleCount = (InternalMultisample::kYes == internalMultisample) ?
-            caps.internalMultisampleCount(format) : 1;
+
+    int sampleCount = 1;
+    if (!caps.mixedSamplesSupport() && InternalMultisample::kYes == internalMultisample) {
+        sampleCount = caps.internalMultisampleCount(format);
+    }
 
     auto instantiate = [cb = std::move(callback), format, sampleCount](GrResourceProvider* rp) {
         return cb(rp, format, sampleCount);