Define the Settings interface for a CrashReportDatabase and provide a Mac implementation.

client/crash_report_database_win.cc

Index: client/crash_report_database_win.cc
diff --git a/client/crash_report_database_win.cc b/client/crash_report_database_win.cc
index 630adb1036574dd6762d5987c282faab03357d10..8dd5908e42cbee3d1b076b75e0bc17c430db2927 100644
--- a/client/crash_report_database_win.cc
+++ b/client/crash_report_database_win.cc
@@ -524,6 +524,7 @@ class CrashReportDatabaseWin : public CrashReportDatabase {
   bool Initialize();
 
   // CrashReportDatabase:
+  Settings* GetSettings() override;
   OperationStatus PrepareNewCrashReport(NewReport** report) override;
   OperationStatus FinishedWritingCrashReport(NewReport* report,
                                              UUID* uuid) override;
@@ -567,6 +568,12 @@ bool CrashReportDatabaseWin::Initialize() {
   return true;
 }
 
+Settings* CrashReportDatabaseWin::GetSettings() {
+  // Port to Win https://code.google.com/p/crashpad/issues/detail?id=13.
+  NOTREACHED();
+  return nullptr;
+}
+
 OperationStatus CrashReportDatabaseWin::PrepareNewCrashReport(
     NewReport** report) {
   ::UUID system_uuid;