ES31: Enable shader storage buffer support for OpenGL backend

BUG=angleproject:1951
TEST=angle_end2end_tests:ShaderStorageBuffer

Change-Id: I1afc3cd005ad2e595c6ce937fc53e17423f8ec8b
Reviewed-on: https://chromium-review.googlesource.com/618132
Commit-Queue: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libANGLE/Compiler.cpp b/src/libANGLE/Compiler.cpp
index 99d7e6b..3baa75c 100644
--- a/src/libANGLE/Compiler.cpp
+++ b/src/libANGLE/Compiler.cpp
@@ -120,6 +120,7 @@
     mResources.MaxAtomicCounterBufferSize      = caps.maxAtomicCounterBufferSize;
 
     mResources.MaxUniformBufferBindings = caps.maxUniformBufferBindings;
+    mResources.MaxShaderStorageBufferBindings = caps.maxShaderStorageBufferBindings;
 
     // Needed by point size clamping workaround
     mResources.MaxPointSize = caps.maxAliasedPointSize;