Revert "DC: Use shader-readable texture when layers disabled."

This reverts commit 7bf349f.

Reason for revert: Seems to have caused crashes on Canary.
BUG=761239

Original change's description:
> DC: Use shader-readable texture when layers disabled.
> 
> Also add a test to cover a bug where a non-shader-readable texture was
> sent to ANGLE. ANGLE has worked around this limitation in [1], but
> it's still helpful to create a compatible texture when possible.
> 
> [1]: https://chromium-review.googlesource.com/638551
> 
> BUG=752917
> 
> Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
> Change-Id: I771f32db459890bb2a0f08cd33ed8770ebf090ca
> Reviewed-on: https://chromium-review.googlesource.com/638911
> Reviewed-by: Antoine Labour <piman@chromium.org>
> Reviewed-by: John Bauman <jbauman@chromium.org>
> Commit-Queue: Jamie Madill <jmadill@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#498131}

TBR=jbauman@chromium.org,jmadill@chromium.org,piman@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 752917
Change-Id: I75b94d1971f213230ccaf540e2b17e684966faa5
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Reviewed-on: https://chromium-review.googlesource.com/648026
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Cr-Commit-Position: refs/heads/master@{#499274}

gpu/ipc/service/direct_composition_child_surface_win.cc

@@ -113,8 +113,7 @@ bool DirectCompositionChildSurfaceWin::InitializeSurface() {
     desc.Stereo = FALSE;
     desc.SampleDesc.Count = 1;
     desc.BufferCount = 2;
-    desc.BufferUsage =
-        DXGI_USAGE_RENDER_TARGET_OUTPUT | DXGI_USAGE_SHADER_INPUT;
+    desc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
     desc.Scaling = DXGI_SCALING_STRETCH;
     desc.SwapEffect = DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL;
     desc.AlphaMode = alpha_mode;

gpu/ipc/service/direct_composition_surface_win_unittest.cc

@@ -472,32 +472,6 @@ class DirectCompositionPixelTest : public testing::Test {
     DestroySurface(std::move(surface_));
   }
 
-  void PixelTestCopyTexture(bool layers_enabled) {
-    if (!CheckIfDCSupported())
-      return;
-    InitializeSurface();
-    surface_->SetEnableDCLayers(layers_enabled);
-    gfx::Size window_size(100, 100);
-
-    scoped_refptr<gl::GLContext> context = gl::init::CreateGLContext(
-        nullptr, surface_.get(), gl::GLContextAttribs());
-    EXPECT_TRUE(surface_->Resize(window_size, 1.0,
-                                 gl::GLSurface::ColorSpace::UNSPECIFIED, true));
-
-    EXPECT_TRUE(surface_->SetDrawRectangle(gfx::Rect(0, 0, 100, 100)));
-    EXPECT_TRUE(context->MakeCurrent(surface_.get()));
-
-    Sleep(1000);
-
-    GLuint texture = 0;
-    glGenTextures(1, &texture);
-    glBindTexture(GL_TEXTURE_2D, texture);
-    glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 0, 0, 100, 100, 0);
-
-    context = nullptr;
-    DestroySurface(std::move(surface_));
-  }
-
   TestPlatformDelegate platform_delegate_;
   TestImageTransportSurfaceDelegate delegate_;
   ui::WinWindow window_;
@@ -512,14 +486,6 @@ TEST_F(DirectCompositionPixelTest, DCLayersDisabled) {
   PixelTestSwapChain(false);
 }
 
-TEST_F(DirectCompositionPixelTest, CopyTextureFromSurfaceWithLayersEnabled) {
-  PixelTestCopyTexture(true);
-}
-
-TEST_F(DirectCompositionPixelTest, CopyTextureFromSurfaceWithLayersDisabled) {
-  PixelTestCopyTexture(false);
-}
-
 bool AreColorsSimilar(int a, int b) {
   // The precise colors may differ depending on the video processor, so allow
   // a margin for error.