Implement a workaround for TF http archives being downloaded multiple times.

While on linux this only saves a minute, on windows this saves 40+ minutes.

PiperOrigin-RevId: 287977569
Change-Id: I795dfa97caee3cde8fea307b56a7b7ebf9e637d7

third_party/repo.bzl

@@ -87,6 +87,15 @@ def _tf_http_archive(ctx):
              "someone will come along shortly thereafter and mirror the file.")
 
     use_syslib = _use_system_lib(ctx, ctx.attr.name)
+
+    # Work around the bazel bug that redownloads the whole library.
+    # Remove this after https://github.com/bazelbuild/bazel/issues/10515 is fixed.
+    if ctx.attr.additional_build_files:
+        for internal_src in ctx.attr.additional_build_files:
+            _ = ctx.path(Label(internal_src))
+
+    # End of workaround.
+
     if not use_syslib:
         ctx.download_and_extract(
             ctx.attr.urls,
@@ -123,10 +132,12 @@ def _tf_http_archive(ctx):
             ctx.symlink(Label(internal_src), ctx.path(external_dest))
 
 tf_http_archive = repository_rule(
-    implementation = _tf_http_archive,
     attrs = {
         "sha256": attr.string(mandatory = True),
-        "urls": attr.string_list(mandatory = True, allow_empty = False),
+        "urls": attr.string_list(
+            mandatory = True,
+            allow_empty = False,
+        ),
         "strip_prefix": attr.string(),
         "type": attr.string(),
         "delete": attr.string_list(),
@@ -139,7 +150,9 @@ tf_http_archive = repository_rule(
     environ = [
         "TF_SYSTEM_LIBS",
     ],
+    implementation = _tf_http_archive,
 )
+
 """Downloads and creates Bazel repos for dependencies.
 
 This is a swappable replacement for both http_archive() and
@@ -204,10 +217,12 @@ def _third_party_http_archive(ctx):
 # For link_files, specify each dict entry as:
 # "//path/to/source:file": "localfile"
 third_party_http_archive = repository_rule(
-    implementation = _third_party_http_archive,
     attrs = {
         "sha256": attr.string(mandatory = True),
-        "urls": attr.string_list(mandatory = True, allow_empty = False),
+        "urls": attr.string_list(
+            mandatory = True,
+            allow_empty = False,
+        ),
         "strip_prefix": attr.string(),
         "type": attr.string(),
         "delete": attr.string_list(),
@@ -220,4 +235,5 @@ third_party_http_archive = repository_rule(
     environ = [
         "TF_SYSTEM_LIBS",
     ],
+    implementation = _third_party_http_archive,
 )