add GLSL syntax highlighting test

tests/syntax-tests/source/GLSL/test.glsl

@@ -0,0 +1,42 @@
+#version 330 core
+
+#ifdef TEST
+layout (location = 0) in vec4 vertex;
+#else
+layout (location = 6) in vec4 vertex;
+#endif
+
+out vec2 p_textureVertex;
+
+/*
+ * This stores offsets
+ */
+struct Data
+{
+    double offsetX;
+    double offsetY;
+}
+
+uniform mat4 projectionMatrix;
+uniform bool test;
+uniform Data data;
+
+double calc()
+{
+    if (test)
+    {
+        return 1.0;
+    }
+    else
+    {
+        return 0.0;
+    }
+}
+
+void main()
+{
+    // This GLSL code serves the purpose of bat syntax highlighting tests
+    double x = data.offsetX + calc();
+    gl_Position = projectionMatrix * vec4(vertex.xy, data.offsetX, data.offsetY);
+    p_textureVertex = vertex.zw;
+}