Bug 958723 - Check for valid FB first. - r=gabadie

content/canvas/src/WebGLContextGL.cpp

@@ -1343,6 +1343,11 @@ WebGLContext::GetFramebufferAttachmentParameter(JSContext* cx,
         return JS::NullValue();
     }
 
+    if (!mBoundFramebuffer) {
+        ErrorInvalidOperation("getFramebufferAttachmentParameter: cannot query framebuffer 0");
+        return JS::NullValue();
+    }
+
     if (attachment != LOCAL_GL_DEPTH_ATTACHMENT &&
         attachment != LOCAL_GL_STENCIL_ATTACHMENT &&
         attachment != LOCAL_GL_DEPTH_STENCIL_ATTACHMENT)
@@ -1365,11 +1370,6 @@ WebGLContext::GetFramebufferAttachmentParameter(JSContext* cx,
         }
     }
 
-    if (!mBoundFramebuffer) {
-        ErrorInvalidOperation("getFramebufferAttachmentParameter: cannot query framebuffer 0");
-        return JS::NullValue();
-    }
-
     MakeContextCurrent();
 
     const WebGLFramebuffer::Attachment& fba = mBoundFramebuffer->GetAttachment(attachment);