Revert "Change default target to "create_sdk"."
Revert "Change default target to "create_sdk"."

This reverts commit 4afb45f5b8db311b199ab3ca5a69af8446f63021.

Reason for revert: Going to instead file a bug to get the `all' target appropriately fixed, if possible.

Original change's description:
> Change default target to "create_sdk".
> 
> Currently the "all" target can lead to build errors and is unsupported,
> so fall back to a supported target instead.
> 
> Change-Id: I925a785e4b81ab92e99c3842cb81c338c5a1d990
> Reviewed-on: https://dart-review.googlesource.com/c/87403
> Auto-Submit: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>
> Reviewed-by: Zach Anderson <zra@google.com>
> Commit-Queue: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>

TBR=zra@google.com,cce218d042444252b7ac446d60910fca7732559c@google.com

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I27c567ad61e54bd2916027b6e27406bd67eb8330
Reviewed-on: https://dart-review.googlesource.com/c/89140
Reviewed-by: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>
Commit-Queue: Stevie Strickland <cce218d042444252b7ac446d60910fca7732559c@google.com>

dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dartino/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dartino/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-lang/sdk,dart-archive/dart-sdk,dart-archive/dart-sdk,dart-lang/sdk,dart-lang/sdk,dartino/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk,dart-archive/dart-sdk,dartino/dart-sdk