Avoid duplicate multisample resolve before WebGL compositing
<rdar://problem/35080724>
Created attachment 324272 [details] Patch
Committed r223707: <https://trac.webkit.org/changeset/223707>
This broke the iOS builds: https://build.webkit.org/builders/Apple%20iOS%2011%20Simulator%20Debug%20%28Build%29/builds/878 https://build.webkit.org/builders/Apple%20iOS%2011%20Simulator%20Debug%20%28Build%29/builds/878/steps/compile-webkit/logs/stdio error: CompileC /Volumes/Data/slave/ios-simulator-11-debug/build/WebKitBuild/WebCore.build/Debug-iphonesimulator/WebCore.build/Objects-normal/x86_64/GraphicsContext3DOpenGLCommon.o platform/graphics/opengl/GraphicsContext3DOpenGLCommon.cpp normal x86_64 c++ com.apple.compilers.llvm.clang.1_0.compiler
iOS build fix in r223711