Use angle::Result in front-end. (Part 1)

This covers most of the hot paths used in draw calls. Gives in the
order of a 5% reduction in draw call overhead.

Bug: angleproject:2491
Change-Id: I2d53afb1163eaceed61fb9cd9ce6c1267c85c0fa
Reviewed-on: https://chromium-review.googlesource.com/c/1258149
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/renderer/d3d/FramebufferD3D.cpp b/src/libANGLE/renderer/d3d/FramebufferD3D.cpp
index 7df422c..ba09d2e 100644
--- a/src/libANGLE/renderer/d3d/FramebufferD3D.cpp
+++ b/src/libANGLE/renderer/d3d/FramebufferD3D.cpp
@@ -322,12 +322,12 @@
     return true;
 }
 
-gl::Error FramebufferD3D::syncState(const gl::Context *context,
-                                    const gl::Framebuffer::DirtyBits &dirtyBits)
+angle::Result FramebufferD3D::syncState(const gl::Context *context,
+                                        const gl::Framebuffer::DirtyBits &dirtyBits)
 {
     if (!mColorAttachmentsForRender.valid())
     {
-        return gl::NoError();
+        return angle::Result::Continue();
     }
 
     for (auto dirtyBit : dirtyBits)
@@ -340,7 +340,7 @@
         }
     }
 
-    return gl::NoError();
+    return angle::Result::Continue();
 }
 
 const gl::AttachmentList &FramebufferD3D::getColorAttachmentsForRender(const gl::Context *context)