Revert "Metal: Test offline-compiled shader link time"

This reverts commit fd03e16d.

Reason for revert: crbug.com/1045444

Original change's description:
> Metal: Test offline-compiled shader link time
> 
> Change metal_util::TestShader to test either compile or link, and
> change the default behavior to link.
> 
> Add inline data for a trivial test shader. Add code to modify the
> bitcode, to defeat caching.
> 
> Ensure that the Metal calls for the test are invoked on a thread
> that has base::TaskPriority::HIGHEST.
> 
> TBR=jvanverth
> 
> Bug: 974219
> Change-Id: I35e688c3758af2e03f893a1ccbef7aef6b778b23
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2015486
> Reviewed-by: ccameron <ccameron@chromium.org>
> Commit-Queue: ccameron <ccameron@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#734645}

TBR=ccameron@chromium.org,jvanverth@chromium.org

Change-Id: I872bad72bfd2bbb4318e032db4b14bf43e14d6e6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 974219
Bug: 1045444
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2020567Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Kai Ninomiya <kainino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735116}

components/metal_util/test_shader.h

@@ -12,13 +12,6 @@
 
 namespace metal {
 
-enum class METAL_UTIL_EXPORT TestShaderComponent {
-  // Test a shader compile from source.
-  kCompile,
-  // Test linking a precompiled shader.
-  kLink,
-};
-
 enum class METAL_UTIL_EXPORT TestShaderResult {
   // Not attempted (e.g, because macOS version does not support Metal).
   kNotAttempted,
@@ -44,7 +37,7 @@ constexpr base::TimeDelta kTestShaderTimeForever =
     base::TimeDelta::FromMinutes(3);
 
 // A default delay before attempting to compile the test shader.
-constexpr base::TimeDelta kTestShaderDelay = base::TimeDelta::FromMinutes(3);
+constexpr base::TimeDelta kTestShaderDelay = base::TimeDelta::FromSeconds(90);
 
 // Attempt to asynchronously compile a trivial Metal shader. If |delay| is zero,
 // then compile synchronously, otherwise, post a delayed task to do the compile.
@@ -58,8 +51,7 @@ constexpr base::TimeDelta kTestShaderDelay = base::TimeDelta::FromMinutes(3);
 void METAL_UTIL_EXPORT
 TestShader(TestShaderCallback callback,
            const base::TimeDelta& delay = kTestShaderDelay,
-           const base::TimeDelta& timeout = kTestShaderTimeout,
-           TestShaderComponent component = TestShaderComponent::kLink);
+           const base::TimeDelta& timeout = kTestShaderTimeout);
 
 }  // namespace metal