[bazel] Bind absl to //external

This simplifies integration with Bazel workspaces that already
have those libraries imported under different repository names.

Change-Id: I6b02cbf6aa7e3582e6a4bf04e3439c05102eb98f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4678629
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/main@{#88858}

BUILD.bazel

@@ -3835,7 +3835,7 @@ cc_library(
     deps = [
         ":torque_base_headers",
         ":v8_libbase",
-        "@com_google_absl//absl/types:optional",
+        "//external:absl_optional",
     ],
 )
 
@@ -3967,8 +3967,8 @@ v8_binary(
         "UNISTR_FROM_CHAR_EXPLICIT=",
     ],
     deps = [
+        "//external:absl_optional",
         "//external:icu",
-        "@com_google_absl//absl/types:optional",
     ],
 )
 

WORKSPACE

@@ -39,6 +39,11 @@ local_repository(
   path = "third_party/abseil-cpp",
 )
 
+bind(
+    name = "absl_optional",
+    actual = "@com_google_absl//absl/types:optional"
+)
+
 new_local_repository(
     name = "com_googlesource_chromium_icu",
     build_file = "bazel/BUILD.icu",