Improve rendering performance of chars with background

Integrate xtermjs/xterm.js#1327 (xtermjs/xterm.js@7c3a30f)

Fixes vercel#2592

Author: chabou

lib/components/term.js

@@ -29,6 +29,7 @@ const getTermOptions = props => {
     fontWeight: props.fontWeight,
     fontWeightBold: props.fontWeightBold,
     allowTransparency: needTransparency,
+    experimentalCharAtlas: 'dynamic',
     theme: {
       foreground: props.foregroundColor,
       background: backgroundColor,

package.json

@@ -199,7 +199,7 @@
     "styled-jsx": "2.2.6",
     "stylis": "3.5.0",
     "uuid": "3.1.0",
-    "xterm": "3.2.0"
+    "xterm": "chabou/xterm.js#b2e393f"
   },
   "devDependencies": {
     "ava": "0.25.0",

yarn.lock

@@ -6693,9 +6693,9 @@ xtend@~2.1.1:
   dependencies:
     object-keys "~0.4.0"
 
-xterm@3.2.0:
-  version "3.2.0"
-  resolved "https://registry.yarnpkg.com/xterm/-/xterm-3.2.0.tgz#da50f54a83d81463c0a2c9f2e0a5d14d3867df02"
+xterm@chabou/xterm.js#b2e393f:
+  version "3.2.0-hyper.0"
+  resolved "https://codeload.github.com/chabou/xterm.js/tar.gz/b2e393f48029ff638d20d2ba6347d0829bd20c42"
 
 y18n@^3.2.1:
   version "3.2.1"