fix: compilation error when chainWebpack's code contains ! (close: #532)

Author: ulivz

package.json

@@ -82,7 +82,7 @@
     "toml": "^2.3.3",
     "url-loader": "^1.0.1",
     "vue": "^2.5.16",
-    "vue-loader": "^15.2.1",
+    "vue-loader": "^15.2.4",
     "vue-router": "^3.0.1",
     "vue-server-renderer": "^2.5.16",
     "vue-template-compiler": "^2.5.16",

yarn.lock

@@ -6683,8 +6683,8 @@ preserve@^0.2.0:
   resolved "https://registry.yarnpkg.com/preserve/-/preserve-0.2.0.tgz#815ed1f6ebc65926f865b310c0713bcb3315ce4b"
 
 prettier@^1.13.0:
-  version "1.13.2"
-  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.13.2.tgz#412b87bc561cb11074d2877a33a38f78c2303cda"
+  version "1.13.4"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.13.4.tgz#31bbae6990f13b1093187c731766a14036fa72e6"
 
 pretty-bytes@^4.0.2:
   version "4.0.2"
@@ -8293,8 +8293,8 @@ vue-jest@^2.6.0:
     vue-template-es2015-compiler "^1.6.0"
 
 vue-loader@^15.2.1:
-  version "15.2.2"
-  resolved "https://registry.yarnpkg.com/vue-loader/-/vue-loader-15.2.2.tgz#d845fef2eca64e91042e66315119536e17f1538d"
+  version "15.2.4"
+  resolved "https://registry.yarnpkg.com/vue-loader/-/vue-loader-15.2.4.tgz#a7b923123d3cf87230a8ff54a1c16d31a6c5dbb4"
   dependencies:
     "@vue/component-compiler-utils" "^1.2.1"
     hash-sum "^1.0.2"