WebGLProgram: Fix `sampler2DArray` precision. (#27854)

src/renderers/webgl/WebGLProgram.js

@@ -870,14 +870,12 @@ function WebGLProgram( renderer, cacheKey, parameters, bindingStates ) {
 
 		prefixVertex = [
 			customVertexExtensions,
-			'precision mediump sampler2DArray;',
 			'#define attribute in',
 			'#define varying out',
 			'#define texture2D texture'
 		].join( '\n' ) + '\n' + prefixVertex;
 
 		prefixFragment = [
-			'precision mediump sampler2DArray;',
 			'#define varying in',
 			( parameters.glslVersion === GLSL3 ) ? '' : 'layout(location = 0) out highp vec4 pc_fragColor;',
 			( parameters.glslVersion === GLSL3 ) ? '' : '#define gl_FragColor pc_fragColor',