gnu: libphonenumber: Build reproducibly.

* gnu/packages/messaging.scm (libphonenumber): Add patch.
* gnu/packages/patches/libphonenumber-reproducible-build.patch: New
file.
* gnu/local.mk (dist_patch_DATA): Register patch.

Signed-off-by: Jonathan Brielmaier <jonathan.brielmaier@web.de>

gnu/local.mk

@@ -1412,6 +1412,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/libmpeg2-global-symbol-test.patch	\
   %D%/packages/patches/libmygpo-qt-fix-qt-5.11.patch		\
   %D%/packages/patches/libmygpo-qt-missing-qt5-modules.patch	\
+  %D%/packages/patches/libphonenumber-reproducible-build.patch	\
   %D%/packages/patches/libqalculate-3.8.0-libcurl-ssl-fix.patch	\
   %D%/packages/patches/libquicktime-ffmpeg.patch 		\
   %D%/packages/patches/librecad-support-for-boost-1.76.patch	\

gnu/packages/messaging.scm

@@ -2782,6 +2782,8 @@ asynchronicity.")
                     (url "https://github.com/google/libphonenumber")
                     (commit (string-append "v" version))))
               (file-name (git-file-name name version))
+              (patches (search-patches
+                        "libphonenumber-reproducible-build.patch"))
               (sha256
                (base32
                 "06y3mh1d1mks6d0ynxp3980g712nkf8l5nyljpybsk326b246hg9"))))
@@ -2803,7 +2805,6 @@ validating international phone numbers.")
    (home-page "https://github.com/google/libphonenumber")
    (license license:asl2.0)))
 
-
 (define-public chatty
  (package
    (name "chatty")

gnu/packages/patches/libphonenumber-reproducible-build.patch

@@ -0,0 +1,25 @@
+Author: Antero Mejr <antero@mailbox.org>
+Upstream status: I didn't report upstream because they don't have an issue tracker and
+PRs require signing the Google CLA. If someone willing to sign the CLA
+wants to submit the patch, please go ahead.
+
+diff --git a/tools/cpp/src/cpp-build/generate_geocoding_data.cc b/tools/cpp/src/cpp-build/generate_geocoding_data.cc
+index 021cf5c8..5948e140 100644
+--- a/tools/cpp/src/cpp-build/generate_geocoding_data.cc
++++ b/tools/cpp/src/cpp-build/generate_geocoding_data.cc
+@@ -88,6 +88,7 @@ class DirEntry {
+
+   const std::string& name() const { return name_; }
+   DirEntryKinds kind() const { return kind_; }
++  bool operator<(const DirEntry& d) { return name_ < d.name(); }
+ 
+  private:
+   std::string name_;
+@@ -115,6 +116,7 @@ bool ListDirectory(const string& path, vector<DirEntry>* entries) {
+     errno = 0;
+     entry = readdir(dir);
+     if (entry == NULL) {
++      std::sort(entries->begin(), entries->end());
+       return errno == 0;
+     }
+     if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) {