Revert "Always build the ANGLE test code. Always build ANGLE on windows and linux."

This reverts commit 238b820369c4b556c2e7c8277855e6950de3d9eb.

Reason for revert: breaks 32-bit bots, iOS bots, Google3 roll, -ASAN bot.

Original change's description:
> Always build the ANGLE test code. Always build ANGLE on windows and linux.
> 
> Make ANGLE test code independent of having ANGLE lib. Make ANGLE test code not include EGL headers.
> 
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=4040
> 
> DOCS_PREVIEW= https://skia.org/?cl=4040
> 
> Change-Id: I7b857e9785246743f53fb969647b1162ce7419ab
> Reviewed-on: https://skia-review.googlesource.com/4040
> Commit-Queue: Brian Salomon <bsalomon@google.com>
> Reviewed-by: Mike Klein <mtklein@chromium.org>
> 

TBR=mtklein@chromium.org,mtklein@google.com,bsalomon@google.com,reviews@skia.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Change-Id: I19bab8c93baebf032f8a4cefbedfe7359317e806
Reviewed-on: https://skia-review.googlesource.com/4758
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
diff --git a/tools/gpu/GrContextFactory.cpp b/tools/gpu/GrContextFactory.cpp
index 63d5f0a..ffc5295 100644
--- a/tools/gpu/GrContextFactory.cpp
+++ b/tools/gpu/GrContextFactory.cpp
@@ -9,7 +9,9 @@
 #include "GrContextFactory.h"
 #include "gl/GLTestContext.h"
 
-#include "gl/angle/GLTestContext_angle.h"
+#if SK_ANGLE
+    #include "gl/angle/GLTestContext_angle.h"
+#endif
 #include "gl/command_buffer/GLTestContext_command_buffer.h"
 #include "gl/debug/DebugGLTestContext.h"
 #if SK_MESA
@@ -114,6 +116,7 @@
                 case kGLES_ContextType:
                     glCtx = CreatePlatformGLTestContext(kGLES_GrGLStandard);
                     break;
+#if SK_ANGLE
                 case kANGLE_D3D9_ES2_ContextType:
                     glCtx = MakeANGLETestContext(ANGLEBackend::kD3D9, ANGLEContextVersion::kES2).release();
                     break;
@@ -129,6 +132,7 @@
                 case kANGLE_GL_ES3_ContextType:
                     glCtx = MakeANGLETestContext(ANGLEBackend::kOpenGL, ANGLEContextVersion::kES3).release();
                     break;
+#endif
                 case kCommandBuffer_ContextType:
                     glCtx = CommandBufferGLTestContext::Create();
                     break;