Revert "Have GrVkRenderTarget only use GrVkAttachments and not derive from GrVkImage."

This reverts commit 3dc6c190dabbe424345f3a8220be87bb92cdaf05.

Reason for revert: hitting assert about RT having input attachment on mali bots

Original change's description:
> Have GrVkRenderTarget only use GrVkAttachments and not derive from GrVkImage.
>
> This change moves the color and resolve attachments used in a
> GrVkRenderTarget to be a GrVkAttachment. These along with the msaa
> attachment now mean that GrVkRenderTarget no longer needs to derive from
> a GrVkImage.
>
> There are a couple ugly things in this CL since GrVkTexture still is a
> GrVkImage since we can't share attachments between GrVkRT and GrVkTex.
> But when that gets updated in the follow on CL things will look much nicer.
>
> Bug: skia:10727
> Change-Id: I2f12674d7517c6d6dea389e2d1fb7296028bcc85
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/379576
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Greg Daniel <egdaniel@google.com>

TBR=egdaniel@google.com,jvanverth@google.com,bsalomon@google.com

Change-Id: Ic46f3947ed9f7b2ca26e8418d643e7f89b6108d2
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:10727
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/380459
Reviewed-by: Greg Daniel <egdaniel@google.com>
Commit-Queue: Greg Daniel <egdaniel@google.com>
diff --git a/src/gpu/GrAttachment.cpp b/src/gpu/GrAttachment.cpp
index 04edf57..6db517d 100644
--- a/src/gpu/GrAttachment.cpp
+++ b/src/gpu/GrAttachment.cpp
@@ -14,28 +14,13 @@
 #include "src/gpu/GrGpu.h"
 
 size_t GrAttachment::onGpuMemorySize() const {
-    // The GrTexture[RenderTarget] is built up by a bunch of attachments each of which are their
-    // own GrGpuResource. Ideally the GrRenderTarget would not be a GrGpuResource and the GrTexture
-    // would just merge with the new GrSurface/Attachment world. Then we could just depend on each
-    // attachment to give its own size since we don't have GrGpuResources owning other
-    // GrGpuResources. Until we get to that point we need to live in some hybrid world. We will let
-    // the msaa and stencil attachments track their own size because they do get cached separately.
-    // For all GrTexture* based things we will continue to to use the GrTexture* to report size and
-    // the owned attachments will have no size and be uncached.
-    // TODO: Once we start using texture attachments this check really should be !texture. However,
-    // until then in GrVkTextureRenderTarget we make a wrapped attachment to use for the render
-    // target which duplicates the GrTexture. These will be merged once we use texture attachments.
-    if ((fSupportedUsages & UsageFlags::kStencilAttachment) ||
-        ((fSupportedUsages & UsageFlags::kColorAttachment) && fSampleCnt > 1)) {
-        GrBackendFormat format = this->backendFormat();
-        SkImage::CompressionType compression = GrBackendFormatToCompressionType(format);
+    GrBackendFormat format = this->backendFormat();
+    SkImage::CompressionType compression = GrBackendFormatToCompressionType(format);
 
-        uint64_t size = GrNumBlocks(compression, this->dimensions());
-        size *= GrBackendFormatBytesPerBlock(this->backendFormat());
-        size *= this->numSamples();
-        return size;
-    }
-    return 0;
+    uint64_t size = GrNumBlocks(compression, this->dimensions());
+    size *= GrBackendFormatBytesPerBlock(this->backendFormat());
+    size *= this->numSamples();
+    return size;
 }
 
 static void build_key(GrResourceKey::Builder* builder,