Merge ARM sysroot install script with existing x86/amd64 one.

.gitignore

 *.gypcmd
 *.mk
 *.ncb
 *.opensdf
 *.props
 *.pyc
 *.rules
 *.sdf
 *.sln
 *.suo
@@ skipping 25 matching lines @@
 # Settings directory for eclipse
 /.settings
 .checkstyle
 cscope.*
 Session.vim
 tags
 Thumbs.db
 v8.log
 /_out
 /android_emulator_sdk
-/arm-sysroot
 /ash/ash_unittests_run.xml
 /base/base_unittests_run.xml
 /breakpad/src/
 /build/Debug
 /build/Debug_x64
 /build/gomacc.lock
 /build/ipch/
 /build/Release
 /build/Release_x64
 /build/win_toolchain.json
@@ skipping 29 matching lines @@
 /chrome/browser/resources/settings_internal/
 /chrome/browser/resources/software_rendering_list
 /chrome/browser/spellchecker/internal
 /chrome/browser_tests_run.xml
 /chrome/chrome_run.xml
 /chrome/chrome_user32_delay_imports.xml
 /chrome/chrome_version_resources.xml
 /chrome/common/extensions/api/api.xml
 /chrome/common/extensions/api/ledger/
 /chrome/Hammer
-/chrome/installer/linux/debian_wheezy_amd64-sysroot/
-/chrome/installer/linux/debian_wheezy_i386-sysroot/
+/chrome/installer/linux/debian_wheezy_*-sysroot/
 /chrome/installer/linux/internal
 /chrome/installer/mac/internal
 /chrome/installer/mac/third_party/xz/xz
 /chrome/installer/mini_installer.xml
 /chrome/installer/mini_installer/mini_installer.aps
 /chrome/installer/mini_installer/support
 /chrome/installer/mini_installer_syzygy.xml
 /chrome/installer/mini_installer_tests_run.xml
 /chrome/installer_util_strings.xml
 /chrome/interactive_ui_tests_run.xml
@@ skipping 317 matching lines @@
 /webkit/data/test_shell/plugins
 /webkit/data/xbm_decoder
 /webkit/Debug
 /webkit/Release
 /webkit/renderer/media/crypto/ppapi/cdm
 /webpagereplay_logs/
 /win8/delegate_execute/delegate_execute_version_resources.xml
 /win8/metro_driver/metro_driver_version_resources.xml
 /x86-generic_out/
 /xcodebuild