Change unshaded logic to match with GLES3

drivers/gles2/rasterizer_canvas_gles2.cpp

@@ -1288,7 +1288,7 @@ void RasterizerCanvasGLES2::canvas_render_items(Item *p_item_list, int p_z, cons
 		}
 
 		int blend_mode = shader_cache ? shader_cache->canvas_item.blend_mode : RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MIX;
-		bool unshaded = (shader_cache && blend_mode != RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MIX);
+		bool unshaded = shader_cache && (shader_cache->canvas_item.light_mode == RasterizerStorageGLES2::Shader::CanvasItem::LIGHT_MODE_UNSHADED || (blend_mode != RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MIX && blend_mode != RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_PMALPHA));
 		bool reclip = false;
 
 		if (last_blend_mode != blend_mode) {