Move other render parts to shared folder

src/browser/renderer/shared/RendererUtils.ts

@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) 2019 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+export function throwIfFalsy<T>(value: T | undefined | null): T {
+  if (!value) {
+    throw new Error('value must not be falsy');
+  }
+  return value;
+}
+
+export function isPowerlineGlyph(codepoint: number): boolean {
+  // Only return true for Powerline symbols which require
+  // different padding and should be excluded from minimum contrast
+  // ratio standards
+  return 0xE0A4 <= codepoint && codepoint <= 0xE0D6;
+}
+
+export function isRestrictedPowerlineGlyph(codepoint: number): boolean {
+  return 0xE0B0 <= codepoint && codepoint <= 0xE0B7;
+}
+
+function isBoxOrBlockGlyph(codepoint: number): boolean {
+  return 0x2500 <= codepoint && codepoint <= 0x259F;
+}
+
+export function excludeFromContrastRatioDemands(codepoint: number): boolean {
+  return isPowerlineGlyph(codepoint) || isBoxOrBlockGlyph(codepoint);
+}