Merge pull request #13744 from takahirox/CleanUpWebGLExtensions

Clean up WebGLExtensions

src/renderers/webgl/WebGLExtensions.js

@@ -36,10 +36,6 @@ function WebGLExtensions( gl ) {
 					extension = gl.getExtension( 'WEBGL_compressed_texture_pvrtc' ) || gl.getExtension( 'WEBKIT_WEBGL_compressed_texture_pvrtc' );
 					break;
 
-				case 'WEBGL_compressed_texture_etc1':
-					extension = gl.getExtension( 'WEBGL_compressed_texture_etc1' );
-					break;
-
 				default:
 					extension = gl.getExtension( name );