Revert "Make createTestingOnlyBackendTexture and deleteTestingOnlyBackendTexture no longer be behind GR_TEST_UTILS"

This reverts commit 50a4e6e3b1289117264c26d66ddaa9862c400acf.

Reason for revert: Chrome fails to compile:

../../third_party/skia/src/gpu/vk/GrVkGpu.cpp:143:29: error: allocating an object of abstract class type 'GrVkGpu'
    return sk_sp<GrGpu>(new GrVkGpu(context, options, backendContext, interface, instanceVersion,
                            ^
../../third_party/skia/src/gpu/GrGpu.h:405:30: note: unimplemented pure virtual method 'createTestingOnlyBackendTexture' in 'GrVkGpu'
    virtual GrBackendTexture createTestingOnlyBackendTexture(int w, int h, const GrBackendFormat&,
                             ^
../../third_party/skia/src/gpu/GrGpu.h:414:18: note: unimplemented pure virtual method 'deleteTestingOnlyBackendTexture' in 'GrVkGpu'
    virtual void deleteTestingOnlyBackendTexture(const GrBackendTexture&) = 0;
                 ^
../../third_party/skia/src/gpu/vk/GrVkGpu.cpp:1525:15: error: out-of-line definition of 'createTestingOnlyVkImage' does not match any declaration in 'GrVkGpu'
bool GrVkGpu::createTestingOnlyVkImage(GrPixelConfig config, int w, int h, bool texturable,
              ^~~~~~~~~~~~~~~~~~~~~~~~
../../third_party/skia/src/gpu/vk/GrVkGpu.cpp:1893:27: error: out-of-line definition of 'createTestingOnlyBackendTexture' does not match any declaration in 'GrVkGpu'
GrBackendTexture GrVkGpu::createTestingOnlyBackendTexture(int w, int h,
                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../third_party/skia/src/gpu/vk/GrVkGpu.cpp:1933:15: error: out-of-line definition of 'deleteTestingOnlyBackendTexture' does not match any declaration in 'GrVkGpu'
void GrVkGpu::deleteTestingOnlyBackendTexture(const GrBackendTexture& tex) {
              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Original change's description:
> Make createTestingOnlyBackendTexture and deleteTestingOnlyBackendTexture no longer be behind GR_TEST_UTILS
> 
> Change-Id: Iec44bc46aa2ab2899af3f6df130a93adf3f26e2a
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/213821
> Commit-Queue: Robert Phillips <robertphillips@google.com>
> Reviewed-by: Greg Daniel <egdaniel@google.com>

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

Change-Id: I6b234ae436842eb292c7a8a725c1a55f3f5fd440
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/214061
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
9 files changed