Enable the ability to change the sandboxee's malloc implementation. T…

…he default is set to "@bazel_tools//tools/cpp:malloc", which is also the default for Bazel's cc_binary [1].

[1] https://bazel.build/reference/be/c-cpp#cc_binary

PiperOrigin-RevId: 583081047
Change-Id: I08e7f6d0dffb1926e7bf9a9a96a7d6727d4cd3d6

sandboxed_api/bazel/sapi.bzl

@@ -236,6 +236,7 @@ def sapi_library(
         name,
         lib,
         lib_name,
+        malloc = "@bazel_tools//tools/cpp:malloc",
         namespace = "",
         api_version = 1,
         embed = True,
@@ -355,6 +356,7 @@ def sapi_library(
             # The sandboxing client must have access to all
             "-Wl,-E",  # symbols used in the sandboxed library, so these
         ] + exported_funcs,  # must be both referenced, and exported
+        malloc = malloc,
         deps = [
             ":" + name + ".lib",
             "//sandboxed_api:client",