Move base32 into base so that it can be used within base.

base/BUILD.gn

Index: base/BUILD.gn
diff --git a/base/BUILD.gn b/base/BUILD.gn
index 88d5d7f036c33d5563b1460dbfe651871816ec04..8a3eb5cceabbf5397f1b7d1db0441c29b527f13b 100644
--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -234,6 +234,8 @@ component("base") {
     "auto_reset.h",
     "barrier_closure.cc",
     "barrier_closure.h",
+    "base32.cc",
+    "base32.h",
     "base64.cc",
     "base64.h",
     "base64url.cc",
@@ -1810,6 +1812,7 @@ test("base_unittests") {
     "at_exit_unittest.cc",
     "atomicops_unittest.cc",
     "barrier_closure_unittest.cc",
+    "base32_unittest.cc",
     "base64_unittest.cc",
     "base64url_unittest.cc",
     "big_endian_unittest.cc",