Android: add NDK hooks

This change adds hooks to key Android support files, so that NDK can
inject information or change cmake behaviors.
37 jobs for !5436 with android-hooks in 6 minutes and 58 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Build
manual #5319740
linux docker cmake build manual
build:centos6-release
passed #5319737
linux docker cmake build
build:debian10-iwyu

00:01:27

manual #5319741
linux docker cmake build linux-3.17 manual
build:fedora31-ninja
passed #5319739
linux docker cmake build linux-3.17
build:fedora31-sphinx

00:05:49

passed #5319738
linux docker cmake build linux-3.17
build:fedora31-tidy

00:06:58

manual #5319743
cmake macos shell nonconcurrent xcode-11.7 manual
build:macos-makefiles
manual #5319742
cmake macos shell nonconcurrent xcode-11.7 manual
build:macos-ninja
manual #5319744
windows cmake shell vs2019 nonconcurrent msvc-19.27 manual
build:windows-vs2019-x64-ninja
 
  Test
created #5319745
linux docker cmake x11 linux-3.17
test:fedora31-ninja
created #5319747
cmake macos shell nonconcurrent xcode-11.7
test:macos-makefiles
created #5319746
cmake macos shell nonconcurrent xcode-11.7
test:macos-ninja
created #5319748
windows cmake shell vs2019 nonconcurrent msvc-19.27
test:windows-vs2019-x64-ninja
 
  Test Ext
created #5319751
linux docker cmake cuda-rt
test:cuda10.2-nvidia
created #5319749
linux docker cmake build linux-3.17
test:debian10-ninja
created #5319750
linux docker cmake build linux-3.17
test:fedora31-makefiles
created #5319752
linux docker cmake build linux-3.17
test:fedora31-ninja-multi
created #5319753
cmake macos shell concurrent xcode-11.7
test:macos-xcode
created #5319754
windows cmake shell vs2019 concurrent msvc-19.27
test:windows-vs2019-x64
 
  External
passed cdash

passed ghostflow-check-master

passed ghostflow-stager

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passed ghostflow-stager

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passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager

passed ghostflow-stager