Merge pull request cocos2d#2826 from VisualSJ/develop-3.5

Arrangement the render mode

Author: dingpinglv

CCBoot.js

@@ -1653,28 +1653,25 @@ cc._initSys = function (config, CONFIG_KEY) {
         var shieldBrowser = [];
         var tmpCanvas = cc.newElement("canvas");
         cc._renderType = cc._RENDER_TYPE_CANVAS;
-        cc._supportRender = true;
+        cc._supportRender = false;
 
         var supportWebGL = win.WebGLRenderingContext;
 
         if(userRenderMode === 2 || (userRenderMode === 0 && supportWebGL && shieldOs.indexOf(sys.os) === -1 && shieldBrowser.indexOf(sys.browserType) === -1))
             try{
                 var context = cc.create3DContext(tmpCanvas, {'stencil': true, 'preserveDrawingBuffer': true });
-                if(context)
+                if(context){
                     cc._renderType = cc._RENDER_TYPE_WEBGL;
-                else
-                    cc._supportRender = false;
-            }catch(e){
-                cc._supportRender = false;
-            }
+                    cc._supportRender = true;
+                }
+            }catch(e){}
 
         if(userRenderMode === 1 || (userRenderMode === 0 && cc._supportRender === false))
             try {
                 tmpCanvas.getContext("2d");
                 cc._renderType = cc._RENDER_TYPE_CANVAS;
-            } catch (e) {
-                cc._supportRender = false;
-            }
+                cc._supportRender = true;
+            } catch (e) {}
     })(sys, config);
 
     sys._canUseCanvasNewBlendModes = function(){