[feature/build-flags] Add build flags support

[felix-schwarz]

Description

Add support for app build flags to enable/disable features at compile time:

• via APP_BUILD_FLAGS in the Xcode project settings
• via app.build-flags in the Branding.plist:

<key>app.build-flags</key>
<string>DISABLE_BACKGROUND_LOCATION</string>

Overview and instructions in doc/APP_BUILD_FLAGS.md.

Also includes fixes from fix/ios12-branded-settings-crash (#1018).

Related Issue

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

[CLAassistant]

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1 out of 2 committers have signed the CLA.

✅ hosy
❌ felix-schwarz
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[michaelstingl]

• via app.build-flags in the Branding.plist

😍 👍

[michaelstingl]

@felix-schwarz in iOS 12 with DISABLE_BACKGROUND_LOCATION, "Background upload notifications" are still visible. I think it should be disabled as well.

[felix-schwarz]

@michaelstingl Thanks! Fixed as of d4e8aa8.

[jesmrec]

Where should be placed the <key>app.build-flags</key> inside the Branding.plist file?

I set it in the first <dict> block of oC online branding file and the background options in Settings(Media Upload) are visible and could be switched on.

What's wrong on my side?

[hosy]

@jesmrec this value will only be used, if the app will be build with fastlane. You placed the key/value pair on the right place, but you have to build the app via fastlane.

[hosy]

@jesmrec should I help you with the fastlane build?

[jesmrec]

Thanks @hosy for your help. Just as info:

To build the app: fastlane owncloud_branding_adhoc_build , by using correct distribution cert.

With the branding parameter

<key>app.build-flags</key>
<string>DISABLE_BACKGROUND_LOCATION</string>

the background location services are disabled:

And the Info.plist does not contain the DISABLE_BACKGROUND_LOCATION stuff

[jesmrec]

So, this is approved on my side