WebGLProgram: Removed glsl version check code.

src/renderers/webgl/WebGLProgram.js

@@ -670,21 +670,6 @@ function WebGLProgram( renderer, cacheKey, parameters, bindingStates ) {
 
 	if ( parameters.isWebGL2 && ! parameters.isRawShaderMaterial ) {
 
-		let isGLSL3ShaderMaterial = false;
-
-		const versionRegex = /^\s*#version\s+300\s+es\s*\n/;
-
-		if ( parameters.isShaderMaterial &&
-			vertexShader.match( versionRegex ) !== null &&
-			fragmentShader.match( versionRegex ) !== null ) {
-
-			isGLSL3ShaderMaterial = true;
-
-			vertexShader = vertexShader.replace( versionRegex, '' );
-			fragmentShader = fragmentShader.replace( versionRegex, '' );
-
-		}
-
 		// GLSL 3.0 conversion
 
 		prefixVertex = [
@@ -697,8 +682,8 @@ function WebGLProgram( renderer, cacheKey, parameters, bindingStates ) {
 		prefixFragment = [
 			'#version 300 es\n',
 			'#define varying in',
-			isGLSL3ShaderMaterial ? '' : 'out highp vec4 pc_fragColor;',
-			isGLSL3ShaderMaterial ? '' : '#define gl_FragColor pc_fragColor',
+			'out highp vec4 pc_fragColor;',
+			'#define gl_FragColor pc_fragColor',
 			'#define gl_FragDepthEXT gl_FragDepth',
 			'#define texture2D texture',
 			'#define textureCube texture',