port 52148c41 (r35407)

  original commit message:
  Add relocatable pointers for wasm memory references that need to be updated when wasm GrowMemory is used. Code generator changes to accept relocatable constants as immediates.

BUG=

Review URL: https://codereview.chromium.org/1895673002

Cr-Commit-Position: refs/heads/master@{#35556}