Add workaround on using non-zero ResolveLevel or ResolveSlice on Metal

Current Metal drivers have a bug that doing MSAA resolve with non-zero
ResolveLevel and ResolveSlice cannot work correctly. This patch adds a
workaround for this bug that first resolving into a temporary one-level
2D texture, then copying the result into the true resolve target.

Although the end2end test ResolveIntoOneMipmapLevelOf2DTexture and
ResolveInto2DArrayTexture can pass on the try bot using AMD GPU, we
find they fail on some other AMD GPUs (Macbook Pro 2018), so currently
this workaround is enabled on all Metal backends.

BUG=dawn:56
TEST=dawn_end2end_tests

Change-Id: Ie85858e58ff486d49dc11c270d8b6d95e216fd42
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/6780
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>

src/dawn_native/Instance.cpp

@@ -73,7 +73,15 @@ namespace dawn_native {
                "Clears texture to full 1 bits as soon as they are created, but doesn't update "
                "the tracking state of the texture. This way we can test the logic of clearing "
                "textures that use recycled memory.",
-               "https://bugs.chromium.org/p/dawn/issues/detail?id=145"}}}};
+               "https://bugs.chromium.org/p/dawn/issues/detail?id=145"}},
+             {Toggle::AlwaysResolveIntoZeroLevelAndLayer,
+              {"always_resolve_into_zero_level_and_layer",
+               "When the resolve target is a texture view that is created on the non-zero level or "
+               "layer of a texture, we first resolve into a temporarily 2D texture with only one "
+               "mipmap level and one array layer, and copy the result of MSAA resolve into the "
+               "true resolve target. This workaround is enabled by default on the Metal drivers "
+               "that have bugs when setting non-zero resolveLevel or resolveSlice.",
+               "https://bugs.chromium.org/p/dawn/issues/detail?id=56"}}}};
 
     }  // anonymous namespace