Merge #17227: Qt: Add Android packaging support

246774e264 depends: fix Qt precompiled headers bug (Igor Cota)
8e7ad4146d depends: disable Qt Vulkan support on Android (Igor Cota)
ba46adaa1a CI: add Android APK build to cirrus (Igor Cota)
7563720e30 CI: add Android APK build script (Igor Cota)
ebfb10cb75 Qt: add Android packaging support (Igor Cota)

Pull request description:

  ![bitcoin-qt](https://user-images.githubusercontent.com/762502/67396157-62f3d000-f5a7-11e9-8a6f-9425823fcd6c.gif)
  This PR is the third and final piece of the basic Android support puzzle - it depends on https://github.com/bitcoin/bitcoin/pull/16110 and is related to https://github.com/bitcoin/bitcoin/pull/16883. It introduces an `android` directory under `qt` and a simple way to build an Android package of `bitcoin-qt`:

  1. Build depends for Android as described in the [README](https://github.com/bitcoin/bitcoin/blob/master/depends/README.md)
  2. Configure with one of the resulting prefixes
  3. Run `make && make apk` in `src/qt`

  The resulting APK files will be in `android/build/outputs/apk`. You can install them manually or with [adb](https://developer.android.com/studio/command-line/adb). One can also open the `android` directory in Android Studio for that integrated development and debugging experience. `BitcoinQtActivity` is your starting point.

  Under the hood makefile `apk` target:

  1. Renames the `bitcoin-qt` binary to `libbitcoin-qt.so` and copies it over to a folder under `android/libs` depending on which prefix and corresponding [ABI](https://developer.android.com/ndk/guides/abis.html#sa) `bitcoin-qt` was built for
  2. Takes `libc++_shared.so` from the Android NDK and puts in the same place. It [must be included](https://developer.android.com/ndk/guides/cpp-support) in the APK
  3. Extracts Qt for Android Java support files from the `qtbase` archive in `depends/sources` to `android/src`

  There is also just a tiny bit of `ifdef`'d code to make the Qt Widgets menus usable. It's not pretty but it works and is a stepping stone towards https://github.com/bitcoin/bitcoin/pull/16883.

ACKs for top commit:
  MarcoFalke:
    cr ACK 246774e264
  laanwj:
    Code review ACK 246774e264

Tree-SHA512: ba30a746576a167545223c35a51ae60bb0838818779fc152c210f5af1413961b2a6ab6af520ff92cbc8dcd5dcb663e81ca960f021218430c1f76397ed4cead6c

depends/packages/qt.mk

@@ -9,7 +9,7 @@ $(package)_qt_libs=corelib network widgets gui plugins testlib
 $(package)_patches=fix_qt_pkgconfig.patch mac-qmake.conf fix_no_printer.patch no-xlib.patch
 $(package)_patches+= fix_android_qmake_conf.patch fix_android_jni_static.patch dont_hardcode_pwd.patch
 $(package)_patches+= drop_lrelease_dependency.patch no_sdk_version_check.patch
-$(package)_patches+= fix_qpainter_non_determinism.patch fix_lib_paths.patch
+$(package)_patches+= fix_qpainter_non_determinism.patch fix_lib_paths.patch fix_android_pch.patch
 
 $(package)_qttranslations_file_name=qttranslations-$($(package)_suffix)
 $(package)_qttranslations_sha256_hash=e1de58ed108b7e0a138815ea60fd46a2c4e1fc31396a707e5630e92de79c53de
@@ -165,6 +165,7 @@ $(package)_config_opts_android += -no-fontconfig
 $(package)_config_opts_android += -L $(host_prefix)/lib
 $(package)_config_opts_android += -I $(host_prefix)/include
 $(package)_config_opts_android += -pch
+$(package)_config_opts_android += -no-feature-vulkan
 
 $(package)_config_opts_aarch64_android += -android-arch arm64-v8a
 $(package)_config_opts_armv7a_android += -android-arch armeabi-v7a
@@ -224,6 +225,7 @@ define $(package)_preprocess_cmds
   patch -p1 -i $($(package)_patch_dir)/fix_no_printer.patch && \
   patch -p1 -i $($(package)_patch_dir)/fix_android_qmake_conf.patch && \
   patch -p1 -i $($(package)_patch_dir)/fix_android_jni_static.patch && \
+  patch -p1 -i $($(package)_patch_dir)/fix_android_pch.patch && \
   patch -p1 -i $($(package)_patch_dir)/no-xlib.patch && \
   patch -p1 -i $($(package)_patch_dir)/fix_qpainter_non_determinism.patch &&\
   patch -p1 -i $($(package)_patch_dir)/no_sdk_version_check.patch && \

depends/patches/qt/fix_android_pch.patch

@@ -0,0 +1,10 @@
+--- old/qtbase/mkspecs/common/android-base-head.conf
++++ new/qtbase/mkspecs/common/android-base-head.conf
+@@ -73,6 +73,6 @@ CROSS_COMPILE = $$NDK_TOOLCHAIN_PATH/bin/$$NDK_TOOLS_PREFIX-
+ QMAKE_PCH_OUTPUT_EXT    = .gch
+
+ QMAKE_CFLAGS_PRECOMPILE       = -x c-header -c ${QMAKE_PCH_INPUT} -o ${QMAKE_PCH_OUTPUT}
+-QMAKE_CFLAGS_USE_PRECOMPILE   = -include ${QMAKE_PCH_OUTPUT_BASE}
++QMAKE_CFLAGS_USE_PRECOMPILE   = -include-pch ${QMAKE_PCH_OUTPUT}
+ QMAKE_CXXFLAGS_PRECOMPILE     = -x c++-header -c ${QMAKE_PCH_INPUT} -o ${QMAKE_PCH_OUTPUT}
+ QMAKE_CXXFLAGS_USE_PRECOMPILE = $$QMAKE_CFLAGS_USE_PRECOMPILE