WebGLPrograms: Avoid warnings with WebGL2.

src/renderers/webgl/WebGLProgram.js

@@ -486,7 +486,7 @@ function WebGLProgram( renderer, cacheKey, parameters ) {
 			parameters.sizeAttenuation ? '#define USE_SIZEATTENUATION' : '',
 
 			parameters.logarithmicDepthBuffer ? '#define USE_LOGDEPTHBUF' : '',
-			parameters.logarithmicDepthBuffer && ( parameters.isWebGL2 || parameters.rendererExtensionFragDepth ) ? '#define USE_LOGDEPTHBUF_EXT' : '',
+			( parameters.logarithmicDepthBuffer && parameters.rendererExtensionFragDepth ) ? '#define USE_LOGDEPTHBUF_EXT' : '',
 
 			'uniform mat4 modelMatrix;',
 			'uniform mat4 modelViewMatrix;',
@@ -612,9 +612,9 @@ function WebGLProgram( renderer, cacheKey, parameters ) {
 			parameters.physicallyCorrectLights ? '#define PHYSICALLY_CORRECT_LIGHTS' : '',
 
 			parameters.logarithmicDepthBuffer ? '#define USE_LOGDEPTHBUF' : '',
-			parameters.logarithmicDepthBuffer && ( parameters.isWebGL2 || parameters.rendererExtensionFragDepth ) ? '#define USE_LOGDEPTHBUF_EXT' : '',
+			( parameters.logarithmicDepthBuffer && parameters.rendererExtensionFragDepth ) ? '#define USE_LOGDEPTHBUF_EXT' : '',
 
-			( parameters.extensionShaderTextureLOD || parameters.envMap ) && ( parameters.isWebGL2 || parameters.rendererExtensionShaderTextureLod ) ? '#define TEXTURE_LOD_EXT' : '',
+			( ( parameters.extensionShaderTextureLOD || parameters.envMap ) && parameters.rendererExtensionShaderTextureLod ) ? '#define TEXTURE_LOD_EXT' : '',
 
 			'uniform mat4 viewMatrix;',
 			'uniform vec3 cameraPosition;',

src/renderers/webgl/WebGLPrograms.js

@@ -284,9 +284,9 @@ function WebGLPrograms( renderer, extensions, capabilities ) {
 			extensionDrawbuffers: material.extensions && material.extensions.drawbuffers,
 			extensionShaderTextureLOD: material.extensions && material.extensions.shaderTextureLOD,
 
-			rendererExtensionFragDepth: extensions.get( 'EXT_frag_depth' ) !== undefined,
-			rendererExtensionDrawBuffers: extensions.get( 'WEBGL_draw_buffers' ) !== undefined,
-			rendererExtensionShaderTextureLod: extensions.get( 'EXT_shader_texture_lod' ) !== undefined,
+			rendererExtensionFragDepth: isWebGL2 || extensions.get( 'EXT_frag_depth' ) !== undefined,
+			rendererExtensionDrawBuffers: isWebGL2 || extensions.get( 'WEBGL_draw_buffers' ) !== undefined,
+			rendererExtensionShaderTextureLod: isWebGL2 || extensions.get( 'EXT_shader_texture_lod' ) !== undefined,
 
 			onBeforeCompile: material.onBeforeCompile