Properly split up animations

[domesticmouse]

This codelab actually has sub steps, but these aren't visible in the generated code. Splitting these out as sub steps so I can update the codelab text with links to individual sub steps.

Pre-launch Checklist

• I read the Effective Dart: Style recently, and have followed its advice.
• I signed the CLA.
• I updated/added relevant documentation (doc comments with ///).
• All existing and new tests are passing.

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[johnpryan]

This is a little hard to review, but am I understanding correctly that each change to the code needs to create a substep folder to be analyzed?

[domesticmouse]

This is a little hard to review, but am I understanding correctly that each change to the code needs to create a substep folder to be analyzed?

Yes, I've inserted copy steps into the middle of your step 2, step 3 to create the partially constructed state you have in the codelab text.

Step 4 required more drastic surgery because you had one patch step that covered multiple steps in the codelab text.

[domesticmouse]

For clarity, the plan going forward is:

1. Land this PR with the broken out sub steps
2. Update the codelab text with references to these new sub steps
3. After the codelab text update is published, create a follow up PR that deletes step_02, step_03 and step_04.

The overall effect of this change is that the individual codeblocks in the codelab will link to sample code that reflects the effect of that specific change. Currently the individual sub steps in step_02 all link to a sample that reflects the finished state of all of the sub steps of step_02.

See Filip's namer sample for an example of another codelab that breaks out individual sub steps.