Fix null pointer access by older Chrome versions.

Older Chrome branches still need the Register() function.

Bug chromium:644329

Change-Id: I6b07aea6e069604f3e5d9e08c97c287df31c0dd6
Reviewed-on: https://swiftshader-review.googlesource.com/7090
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
(cherry picked from commit 95db80e4269db8ee31432590defa699d6dd36f6b)
Reviewed-on: https://swiftshader-review.googlesource.com/7091
Reviewed-by: Nicolas Capens <capn@google.com>
diff --git a/src/OpenGL/libGLESv2/main.cpp b/src/OpenGL/libGLESv2/main.cpp
index 12ed31d..7537c15 100644
--- a/src/OpenGL/libGLESv2/main.cpp
+++ b/src/OpenGL/libGLESv2/main.cpp
@@ -1325,6 +1325,11 @@
 {
 	return es2::DrawBuffersEXT(n, bufs);
 }
+
+void GL_APIENTRY Register(const char *licenseKey)
+{
+	// Nothing to do, SwiftShader is open-source
+}
 }
 
 egl::Context *es2CreateContext(egl::Display *display, const egl::Context *shareContext, int clientVersion);