8198697: Simplify initialization of platform encoding
Reviewed-by: redestad, sherman
## Pako v1.0### Pako License<pre>Copyright (C) 2014-2017 by Vitaly Puzrin and Andrei TuputcynPermission is hereby granted, free of charge, to any person obtaining a copyof this software and associated documentation files (the "Software"), to dealin the Software without restriction, including without limitation the rightsto use, copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom the Software isfurnished to do so, subject to the following conditions:The above copyright notice and this permission notice shall be included inall copies or substantial portions of the Software.THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THEAUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHERLIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS INTHE SOFTWARE.(C) 1995-2013 Jean-loup Gailly and Mark Adler(C) 2014-2017 Vitaly Puzrin and Andrey TupitsinThis software is provided 'as-is', without any express or impliedwarranty. In no event will the authors be held liable for any damagesarising from the use of this software.Permission is granted to anyone to use this software for any purpose,including commercial applications, and to alter it and redistribute itfreely, subject to the following restrictions:1. The origin of this software must not be misrepresented; you must notclaim that you wrote the original software. If you use this softwarein a product, an acknowledgment in the product documentation would beappreciated but is not required.2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.3. This notice may not be removed or altered from any source distribution.</pre>