Convert GrManyDependentsMipMappedTest to a mock gpu test

This allows us to test with fReduceOpListSplitting both enabled and
disabled.

This CL also requires adding basic mipmap support to GrMockGpu.

Bug: skia:
Change-Id: I97ba912a9e5f3b90756c027ac19c003c99c15902
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/235996
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Robert Phillips <robertphillips@google.com>
diff --git a/src/gpu/mock/GrMockTexture.h b/src/gpu/mock/GrMockTexture.h
index f954f58..44c05ad 100644
--- a/src/gpu/mock/GrMockTexture.h
+++ b/src/gpu/mock/GrMockTexture.h
@@ -93,7 +93,10 @@
         this->registerWithCacheWrapped(GrWrapCacheable::kNo);
     }
 
-    ResolveType getResolveType() const override { return kCanResolve_ResolveType; }
+    ResolveType getResolveType() const override {
+        return (this->requiresManualMSAAResolve()) ?
+                kCanResolve_ResolveType : kAutoResolves_ResolveType;
+    }
     bool canAttemptStencilAttachment() const override { return true; }
     bool completeStencilAttachment() override { return true; }