Revert "[Fuchsia] Remove checkout_fuchsia_for_arm64_host"

This reverts commit 6cd14492.

Reason for revert: The build roll is breaking out Android Arm64 build (https://ci.chromium.org/ui/p/v8/builders/ci/V8%20Android%20Arm64%20-%20builder/41853/overview)

Original change's description:
> [Fuchsia] Remove checkout_fuchsia_for_arm64_host
>
> Also roll /build to a version that contains the cl removing
> checkout_fuchsia_for_arm64_host
>
> Bug: chromium:1137662
> Change-Id: I72851e5ab4e1daabf6ea62fb7935dfd28d8dee25
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3232816
> Auto-Submit: Chong Gu <chonggu@google.com>
> Commit-Queue: Chong Gu <chonggu@google.com>
> Reviewed-by: Michael Achenbach <machenbach@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#77486}

Bug: chromium:1137662
Change-Id: I48f8f030cee277b761d17fa3c891737f84c25970
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3234962
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Owners-Override: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77487}

DEPS

@@ -6,6 +6,9 @@ use_relative_paths = True
 
 gclient_gn_args_file = 'build/config/gclient_args.gni'
 gclient_gn_args = [
+  # TODO(https://crbug.com/1137662, https://crbug.com/1080854)
+  # Remove when migration is complete.
+  'checkout_fuchsia_for_arm64_host',
 ]
 
 vars = {
@@ -24,6 +27,12 @@ vars = {
   # Wildcards are supported (e.g. "qemu.*").
   'checkout_fuchsia_boot_images': "qemu.x64,qemu.arm64",
 
+  # TODO(https://crbug.com/1137662, https://crbug.com/1080854)
+  # Remove when migration is complete.
+  # By default, do not check out files required to run fuchsia tests in
+  # qemu on linux-arm64 machines.
+  'checkout_fuchsia_for_arm64_host': False,
+
   'checkout_instrumented_libraries': False,
   'checkout_ittapi': False,
   # Fetch clang-tidy into the same bin/ directory as our clang binary.
@@ -83,7 +92,7 @@ deps = {
   'base/trace_event/common':
     Var('chromium_url') + '/chromium/src/base/trace_event/common.git' + '@' + '68d816952258c9d817bba656ee2664b35507f01b',
   'build':
-    Var('chromium_url') + '/chromium/src/build.git' + '@' + '110f470441bc9851b31f6b78c55dd8b2dfdef829',
+    Var('chromium_url') + '/chromium/src/build.git' + '@' + 'f78b0bd09847b94e9ec9cb520855d6785fd082ab',
   'buildtools':
     Var('chromium_url') + '/chromium/src/buildtools.git' + '@' + 'a9bc3e283182a586998338a665c7eae17406ec54',
   'buildtools/clang_format/script':