[core] Make MapDebugOptions::Overdraw a no-op in Release mode

src/mbgl/renderer/painter.cpp

@@ -46,7 +46,9 @@ Painter::Painter(const TransformState& state_,
     gl::debugging::enable();
 
     shaders = std::make_unique<Shaders>(store);
+#if defined(DEBUG)
     overdrawShaders = std::make_unique<Shaders>(store, Shader::Overdraw);
+#endif
 
     // Reset GL values
     config.setDirty();
@@ -69,7 +71,11 @@ void Painter::render(const Style& style, const FrameData& frame_, SpriteAtlas& a
     frame = frame_;
 
     PaintParameters parameters {
+#if defined(DEBUG)
         isOverdraw() ? *overdrawShaders : *shaders
+#else
+        *shaders
+#endif
     };
 
     glyphAtlas = style.glyphAtlas.get();

src/mbgl/renderer/painter.hpp

@@ -139,7 +139,11 @@ private:
 
     void setDepthSublayer(int n);
 
+#if defined(DEBUG)
     bool isOverdraw() const { return frame.debugOptions & MapDebugOptions::Overdraw; }
+#else
+    bool isOverdraw() const { return false; }
+#endif
 
     mat4 projMatrix;
 
@@ -174,7 +178,9 @@ private:
     FrameHistory frameHistory;
 
     std::unique_ptr<Shaders> shaders;
+#if defined(DEBUG)
     std::unique_ptr<Shaders> overdrawShaders;
+#endif
 
     // Set up the stencil quad we're using to generate the stencil mask.
     StaticVertexBuffer tileStencilBuffer {