Add base::ExecutableExistsInPath

net/proxy/proxy_config_service_linux.cc

Index: net/proxy/proxy_config_service_linux.cc
diff --git a/net/proxy/proxy_config_service_linux.cc b/net/proxy/proxy_config_service_linux.cc
index db65567a3ecb5f10b96a4a6cb6f01bb664dd3b57..7387c357941f6c63ae90bd2a9e84b65396bc066c 100644
--- a/net/proxy/proxy_config_service_linux.cc
+++ b/net/proxy/proxy_config_service_linux.cc
@@ -19,7 +19,6 @@
 #include "base/bind.h"
 #include "base/compiler_specific.h"
 #include "base/debug/leak_annotations.h"
-#include "base/environment.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/files/scoped_file.h"
@@ -29,7 +28,6 @@
 #include "base/nix/xdg_util.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
-#include "base/strings/string_split.h"
 #include "base/strings/string_tokenizer.h"
 #include "base/strings/string_util.h"
 #include "base/threading/thread_restrictions.h"
@@ -834,23 +832,15 @@ bool SettingGetterImplGSettings::LoadAndCheckVersion(
   }
   g_object_unref(client);
 
-  std::string path;
-  if (!env->GetVar("PATH", &path)) {
-    LOG(ERROR) << "No $PATH variable. Assuming no gnome-network-properties.";
-  } else {
-    // Yes, we're on the UI thread. Yes, we're accessing the file system.
-    // Sadly, we don't have much choice. We need the proxy settings and we
-    // need them now, and to figure out where to get them, we have to check
-    // for this binary. See http://crbug.com/69057 for additional details.
+  // Yes, we're on the UI thread. Yes, we're accessing the file system.
+  // Sadly, we don't have much choice. We need the proxy settings and we
+  // need them now, and to figure out where to get them, we have to check
+  // for this binary. See http://crbug.com/69057 for additional details.
+  {
     base::ThreadRestrictions::ScopedAllowIO allow_io;
-
-    for (const base::StringPiece& path_str : base::SplitStringPiece(
-             path, ":", base::KEEP_WHITESPACE, base::SPLIT_WANT_NONEMPTY)) {
-      base::FilePath file(path_str);
-      if (base::PathExists(file.Append("gnome-network-properties"))) {
-        VLOG(1) << "Found gnome-network-properties. Will fall back to gconf.";
-        return false;
-      }
+    if (base::ExecutableExistsInPath("gnome-network-properties")) {

[mattm, 2016/06/22 21:12:25]

This should probably accept the Environment to use as an argument? That would
avoid having to re-do the parsing if you already have one like here. 

Also the unittest uses a mock environment for testing. It doesn't seem to test
this condition explicitly but it might depend on it anyway. (eg, it may
pass/fail depending on whether the test system has the binary in path. I haven't
tried to verify if that actually happens but it seems worth preserving the old
behavior in any case.)

+      VLOG(1) << "Found gnome-network-properties. Will fall back to gconf.";
+      return false;
     }
   }