Resolved duplicated reference ShareFolderActivity error.

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What does this implement/fix? Explain your changes.

…

After git clone & run the project, there's an error:

duplicate symbol '_OBJC_CLASS_$_ShareFolderActivity' in...

Does this close any currently open issues?

… No

Any relevant logs, error output, etc?

duplicate symbol '_OBJC_CLASS_$_ShareFolderActivity' in:
    /Users/william/Library/Developer/Xcode/DerivedData/iMEGA-bctrlrizxbfwecbtggrlpwmjmxrx/Build/Intermediates.noindex/MEGA.build/Debug-iphonesimulator/MEGA.build/Objects-normal/x86_64/ShareFolderActivity-A5049519A0376D76.o
duplicate symbol '_OBJC_METACLASS_$_ShareFolderActivity' in:
    /Users/william/Library/Developer/Xcode/DerivedData/iMEGA-bctrlrizxbfwecbtggrlpwmjmxrx/Build/Intermediates.noindex/MEGA.build/Debug-iphonesimulator/MEGA.build/Objects-normal/x86_64/ShareFolderActivity-A5049519A0376D76.o
duplicate symbol '_OBJC_IVAR_$_ShareFolderActivity._nodes' in:
    /Users/william/Library/Developer/Xcode/DerivedData/iMEGA-bctrlrizxbfwecbtggrlpwmjmxrx/Build/Intermediates.noindex/MEGA.build/Debug-iphonesimulator/MEGA.build/Objects-normal/x86_64/ShareFolderActivity-A5049519A0376D76.o
ld: 3 duplicate symbols for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Any other comments?

…

There's another issue when run this project under XCode 11.4:

MEGA/iOS/MEGA.xcodeproj Building for iOS Simulator, but the linked library 'libcryptopp.a' was built for iOS.

The solution is changingworkspace settings from New Build System to Legacy Build System then the error is gone.

Not included in this PR.

Where has this been tested?

Devices/Simulators: … iPhone SE(2nd generation) Simulator iOS Version: … iOS 13.4.1 MEGA Version: … lastest master branch.

meganz / iOS