Revert "Temporarily disable isolated splits to get canary coverage"

This reverts commit a5819cfe.

Reason for revert: This was temporary, canaries look stable.

Original change's description:
> Temporarily disable isolated splits to get canary coverage
>
> We are planning on running binary experiments for isolated splits
> enabled/disabled on M89. I want to make sure there are no problems with
> the disabled version before branch cut. I'll revert this CL after a
> couple days.
>
> Bug: 1150162
> Change-Id: I20061a079e897058625506dab810c4584c200fec
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2618367
> Commit-Queue: Clark DuVall <cduvall@chromium.org>
> Reviewed-by: Andrew Grieve <agrieve@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#841596}

TBR=agrieve@chromium.org,cduvall@chromium.org,chromium-scoped@luci-project-accounts.iam.gserviceaccount.com

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

Bug: 1150162
Change-Id: I9b7dfb6851df6264e0a7cfd8d1c17a266d4cdbb7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2621993Reviewed-by: Clark DuVall <cduvall@chromium.org>
Commit-Queue: Clark DuVall <cduvall@chromium.org>
Cr-Commit-Position: refs/heads/master@{#842119}

chrome/android/modules/buildflags.gni

@@ -13,7 +13,8 @@ declare_args() {
   # other DFMs.
   # TODO(crbug.com/1126301): The binary size tools need to be updated to include
   # DFM code before this can be enabled on stable.
-  enable_chrome_module = false
+  enable_chrome_module = android_channel == "default" ||
+                         android_channel == "canary" || android_channel == "dev"
 
   # Whether to enable DFMs which depend on the chrome DFM. These will be split
   # out of the chrome DFM using DexSplitter.