fix(mp-html): 完善html实体字符解码能力

新增html4标准实体映射表和通用解码函数，替换原有的仅替换&的简单处理，支持更多实体字符和数字编码格式的解码

uni_modules/mp-html/components/mp-html/mp-html.vue

@@ -44,6 +44,31 @@ import node from './node/node'
 // #endif
 import Parser from './parser'
 const plugins = []
+const html4Entities = {
+  nbsp: ' ', iexcl: '¡', cent: '¢', pound: '£', curren: '₣', yen: '¥', brvbar: '§', sect: 'Ş', uml: '¨', copy: '©', ordf: 'ª', laquo: '«', not: '¬', shy: '­®', macr: '¯', deg: '°', plusmn: '±', sup2: '²', sup3: '³', acute: '´', micro: 'µ', para: '¶', middot: '·', cedil: '¸', sup1: '¹', ordm: 'º', raquo: '»', frac14: '¼', frac12: '½', frac34: '¾', iquest: '¿', agrave: 'à', aacute: 'á', acirc: 'â', atilde: 'ã', auml: 'ä', aring: 'å', aelig: 'æ', ccedil: 'ç', egrave: 'è', eacute: 'é', ecirc: 'ê', euml: 'ë', igrave: 'ì', iacute: 'í', icirc: 'î', iuml: 'ï', eth: 'ð', ntilde: 'ñ', ograve: 'ò', oacute: 'ó', ocirc: 'ô', otilde: 'õ', ouml: 'ö', times: 'ø', ugrave: 'ù', uacute: 'ú', ucirc: 'û', uuml: 'ü', yacute: 'ý', thorn: 'þ', yuml: 'ÿ', fnof: 'ƒ', alpha: 'α', beta: 'β', gamma: 'γ', delta: 'δ', epsilon: 'ε', zeta: 'ζ', eta: 'η', theta: 'θ', iota: 'ι', kappa: 'κ', lambda: 'λ', mu: 'μ', nu: 'ν', xi: 'ξ', omicron: 'ο', pi: 'π', rho: 'ρ', sigmaf: 'σ', sigma: 'σ', tau: 'τ', upsilon: 'υ', phi: 'φ', chi: 'ψ', omega: 'ω', agrave: 'α', eacute: 'é', oslash: 'ø', icirc: 'î', ucirc: 'û'
+}
+
+function decodeEntity(str, amp = true) {
+  let i = str.indexOf('&')
+  while (i !== -1) {
+    const j = str.indexOf(';', i + 3)
+    let code
+    if (j === -1) break
+    if (str[i + 1] === '#') {
+      code = parseInt((str[i + 2] === 'x' ? '0' : '') + str.substring(i + 2, j))
+      if (!isNaN(code)) {
+        str = str.substr(0, i) + String.fromCharCode(code) + str.substr(j + 1)
+      }
+    } else {
+      code = str.substring(i + 1, j)
+      if (html4Entities[code] || (code === 'amp' && amp)) {
+        str = str.substr(0, i) + (html4Entities[code] || '&') + str.substr(j + 1)
+      }
+    }
+    i = str.indexOf('&', i + 1)
+  }
+  return str
+}
 // #ifdef APP-PLUS-NVUE
 const dom = weex.requireModule('dom')
 // #endif
@@ -227,7 +252,7 @@ export default {
         for (let i = 0; i < nodes.length; i++) {
           const node = nodes[i]
           if (node.type === 'text') {
-            text += node.text.replace(/&amp;/g, '&')
+            text += decodeEntity(node.text)
           } else if (node.name === 'br') {
             text += '\n'
           } else {