On windows, build zlib as a static library.

Partially in preparation for building libpng on Windows.

Also, this makes us consistent across platforms for PDF.

Uses the version of zlib checked into the Chromium tree.

Remove miniz, which is replaced by zlib.

Review URL: https://codereview.chromium.org/966963002
diff --git a/DEPS b/DEPS
index c4068db..3c16bd9 100644
--- a/DEPS
+++ b/DEPS
@@ -16,7 +16,8 @@
   "third_party/externals/jsoncpp" : "https://chromium.googlesource.com/external/jsoncpp/jsoncpp.git@1afff032c83e26ddf7f2776e8b43de5ad666c1fa",
   "third_party/externals/libjpeg" : "https://chromium.googlesource.com/chromium/deps/libjpeg_turbo.git@82ce8a6d4ebe12a177c0c3597192f2b4f09e81c3",
   "third_party/externals/libwebp" : "https://chromium.googlesource.com/webm/libwebp.git@3fe91635df8734b23f3c1b9d1f0c4fa8cfaf4e39",
-  "third_party/externals/nanomsg": "https://skia.googlesource.com/third_party/nanomsg.git@0.4-beta",
+  "third_party/externals/nanomsg" : "https://skia.googlesource.com/third_party/nanomsg.git@0.4-beta",
+  "third_party/externals/zlib"    : "https://chromium.googlesource.com/chromium/src/third_party/zlib@4ba7cdd0e7bf49d671645264f839838fc56e1492",
 
   "platform_tools/android/third_party/externals/expat" : "https://android.googlesource.com/platform/external/expat.git@android-4.2.2_r1.2",
   "platform_tools/android/third_party/externals/gif" : "https://android.googlesource.com/platform/external/giflib.git@android-4.2.2_r1.2",