Fixes to be compatible with android-ndk-18.

Author: virxkane

android/app/build.gradle

@@ -13,7 +13,6 @@ android {
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
         externalNativeBuild {
             cmake {
-                arguments "-DANDROID_TOOLCHAIN=clang"
                 arguments "-DANDROID_STL=c++_static"
                 cppFlags ""
             }
@@ -61,13 +60,7 @@ android {
                 }
             }
             packagingOptions{
-                doNotStrip "*/armeabi/*.so"
-                doNotStrip "*/armeabi-v7a/*.so"
-                doNotStrip "*/arm64-v8a/*.so"
-                doNotStrip "*/x86/*.so"
-                doNotStrip "*/x86_64/*.so"
-                doNotStrip "*/mips/*.so"
-                doNotStrip "*/mips64/*.so"
+                doNotStrip "*/*/*.so"
             }
         }
     }

android/jni/Application.mk

@@ -21,6 +21,4 @@ APP_ABI := arm64-v8a
 APP_PLATFORM := android-8
 #APP_PLATFORM := android-3
 
-NDK_TOOLCHAIN_VERSION := 4.9
-
 APP_STL := c++_static

thirdparty/libpng/pnglibconf.h

@@ -208,7 +208,9 @@
 #define PNG_USER_HEIGHT_MAX 1000000
 #define PNG_USER_WIDTH_MAX 1000000
 #define PNG_ZBUF_SIZE 8192
-#define PNG_ZLIB_VERNUM 0x1230
+// Replaced autodetected PNG_ZLIB_VERNUM 0x1230 (libpng configured with ndk-16b API14) 
+//   to '0' to suppress errors in ndk-18 with newer zlib.
+#define PNG_ZLIB_VERNUM 0
 #define PNG_Z_DEFAULT_COMPRESSION (-1)
 #define PNG_Z_DEFAULT_NOFILTER_STRATEGY 0
 #define PNG_Z_DEFAULT_STRATEGY 1