Move all callers of GetHomeDir() to PathService::Get(base::DIR_HOME).

content/browser/ppapi_plugin_process_host.cc

Index: content/browser/ppapi_plugin_process_host.cc
diff --git a/content/browser/ppapi_plugin_process_host.cc b/content/browser/ppapi_plugin_process_host.cc
index 39c6bc30205244703b847bb2f21fa11dcab55373..a8e0c8d78451fe610b7bd458f81443d7f9ac4ba6 100644
--- a/content/browser/ppapi_plugin_process_host.cc
+++ b/content/browser/ppapi_plugin_process_host.cc
@@ -6,10 +6,12 @@
 
 #include <string>
 
+#include "base/base_paths.h"
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/metrics/field_trial.h"
+#include "base/path_service.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/browser/browser_child_process_host_impl.h"
 #include "content/browser/plugin_service_impl.h"
@@ -306,6 +308,13 @@ bool PpapiPluginProcessHost::Init(const PepperPluginInfo& info) {
                                          : switches::kPpapiPluginProcess);
   cmd_line->AppendSwitchASCII(switches::kProcessChannelID, channel_id);
 
+#if defined(OS_CHROMEOS)
+  // On Chrome OS need to pass primary user homedir.

[Will Drewry, 2014/04/08 15:55:04]

What does PPAPI use the home dir for?  What sort of side effects can it have on
the primary user data?

[Nikita (slow), 2014/04/08 16:40:08]

This doesn't change how it is implemented right now since now it is using
GetHomeDir() which returns /home/chronos/user which is the primary user home
dir.

I don't know what they used it for, here's the snippet
https://code.google.com/p/chromium/codesearch#chromium/src/content/ppapi_plug...

// Specifies $HOME explicitly because some plugins rely on $HOME but
// no other part of Chrome OS uses that.  See crbug.com/335290.

https://code.google.com/p/chromium/issues/detail?id=335290 mentions
ScreenshotTaker.

+  base::FilePath homedir;
+  PathService::Get(base::DIR_HOME, &homedir);
+  cmd_line->AppendSwitchASCII(switches::kHomedir, homedir.value().c_str());
+#endif
+
   // These switches are forwarded to both plugin and broker pocesses.
   static const char* kCommonForwardSwitches[] = {
     switches::kVModule