Working directory FileSpec should use remote path syntax to display correctly.

[chaoren]

Summary

Depends on D9728.

[clayborg]

lgtm

[chaoren]

Rebasing on top of D9728.

include/lldb/Host/FileSpec.h

public:
     /// @param[in] resolve_path
     ///     If \b true, then we will try to resolve links the path using
     ///     the static FileSpec::Resolve.
     //------------------------------------------------------------------
     void
     SetFile (const char *path, bool resolve_path, PathSyntax syntax = ePathSyntaxHostNative);
 
     void
+    SetFile(const char *path, bool resolve_path, ArchSpec arch);
+
+    void
     SetFile(const std::string &path, bool resolve_path, PathSyntax syntax = ePathSyntaxHostNative);
 
+    void
+    SetFile(const std::string &path, bool resolve_path, ArchSpec arch);
+
     bool
     IsResolved () const
     {
         return m_is_resolved;
     }
 
     //------------------------------------------------------------------
     /// Set if the file path has been resolved or not.

source/Host/common/FileSpec.cpp

if (!filename_ref.empty())
         if (!directory_ref.empty())
             m_directory.SetString(directory_ref);
     }
     else
         m_directory.SetCString(normalized.c_str());
 }
 
 void
+FileSpec::SetFile(const char *pathname, bool resolve, ArchSpec arch)
+{
+    return SetFile(pathname, resolve,
+            arch.GetTriple().isOSWindows()
+            ? ePathSyntaxWindows
+            : ePathSyntaxPosix);
+}
+
+void
 FileSpec::SetFile(const std::string &pathname, bool resolve, PathSyntax syntax)
 {
     return SetFile(pathname.c_str(), resolve, syntax);
 }
 
+void
+FileSpec::SetFile(const std::string &pathname, bool resolve, ArchSpec arch)
+{
+    return SetFile(pathname.c_str(), resolve, arch);
+}
+
 //----------------------------------------------------------------------
 // Convert to pointer operator. This allows code to check any FileSpec
 // objects to see if they contain anything valid using code such as:
 //
 //  if (file_spec)
 //  {}
 //----------------------------------------------------------------------
 FileSpec::operator bool() const

source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.cpp

GDBRemoteCommunicationClient::GetWorkingDir(FileSpec &working_dir)
     if (SendPacketAndWaitForResponse ("qGetWorkingDir", response, false) == PacketResult::Success)
     {
         if (response.IsUnsupportedResponse())
             return false;
         if (response.IsErrorResponse())
             return false;
         std::string cwd;
         response.GetHexByteString(cwd);
-        working_dir.SetFile(cwd, false);
+        working_dir.SetFile(cwd, false, GetHostArchitecture());
         return !cwd.empty();
     }
     return false;
 }
 
 int
 GDBRemoteCommunicationClient::SetWorkingDir(const FileSpec &working_dir)
 {