Revert "Make FlutterFragment usable without requiring it to be attached to an Android Activity."

[zanderso]

Reverts #27332

I don't know why this didn't fail in presubmit:

https://ci.chromium.org/ui/p/flutter/builders/prod/Linux%20Unopt/647/overview

../../flutter/shell/platform/android/test/io/flutter/embedding/android/FlutterActivityAndFragmentDelegateTest.java:393: error: method onCreateView in class FlutterActivityAndFragmentDelegate cannot be applied to given types;
    delegate.onCreateView(null, null, null);
            ^
  required: LayoutInflater,ViewGroup,Bundle,int
  found: <null>,<null>,<null>
  reason: actual and formal argument lists differ in length
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error

/cc @ajmalk

[zanderso]

Reverting tip-of-tree commit without running presubmits to green the tree.

[dnfield]

LGTM

[dnfield]

This fails locally after merging up with master - it seems like the patch may have been against an older version of master and worked in presubmit, but failed when merging to head.

[dnfield]

Yeah that's exactly what happened.

[ajmalk]

Oh man just my luck. 🙃

Attempt 2: #27397

[ajmalk]

You might want to reopen flutter/flutter#85326. I don't think I have permission to do that?

[dnfield]

I already opened a reland of this here: #27386