docs($compile): Fix a typo in the warning header

Closes angular#15184

Author: Adrian Bordinc

src/ng/compile.js

@@ -8,7 +8,7 @@
  *                                                                         *
  *  Does the change somehow allow for arbitrary javascript to be executed? *
  *    Or allows for someone to change the prototype of built-in objects?   *
- *     Or gives undesired access to variables likes document or window?    *
+ *     Or gives undesired access to variables like document or window?    *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
 /* ! VARIABLE/FUNCTION NAMING CONVENTIONS THAT APPLY TO THIS FILE!