Fold both PromoteInitializersToConstVar and VarForDynamicIndex into this
new transform, with a config to enable either type of transformation.
This is almost a no-op change, except that VarForDynamicIndex required
ForLoopToLoop, while this tranformation in PromoteInitializersToConstVar
converts for-loops only as needed, so it doesn't do so when the
expression is in the for-loop initializer.
This transform will be extended to handle ensuring order of execution of
expressions.
Bug: tint:1300
Change-Id: I4d00984346a2c92b2d8563b459898f8f737589fd
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/77140
Reviewed-by: Ben Clayton <bclayton@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>