Force migrate all clients from multi-install back to single-install.

chrome/test/mini_installer/config/chrome_system_installed.prop

 {
   "Files": {
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\chrome.exe": {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\chrome.VisualElementsManifest.xml": {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\chrome.dll":
         {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\chrome_elf.dll":
         {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\Installer\\chrome.7z":
         {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\Installer\\setup.exe":
         {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\$MINI_INSTALLER_FILE_VERSION.manifest":
         {"exists": true},
     "$PROGRAM_FILES\\$CHROME_DIR\\Application\\$NEXT_VERSION_MINI_INSTALLER_FILE_VERSION":
         {"exists": false}
   },
   "RegistryEntries": {
     "HKEY_LOCAL_MACHINE\\$CHROME_UPDATE_REGISTRY_SUBKEY": {
       "exists": "required",
       "values": {
         "pv": {"type": "SZ", "data": "$MINI_INSTALLER_FILE_VERSION"}
       }
     },
     "HKEY_LOCAL_MACHINE\\$BINARIES_UPDATE_REGISTRY_SUBKEY": {
-      "exists": "required",
-      "values": {
-        "pv": {"type": "SZ", "data": "$MINI_INSTALLER_FILE_VERSION"}
-      }
+      "exists": "forbidden"
     },
     "HKEY_LOCAL_MACHINE\\$LAUNCHER_UPDATE_REGISTRY_SUBKEY": {
       "condition": "'$CHROME_SHORT_NAME' == 'Chrome'",
       "exists": "forbidden"
     },
     "HKEY_LOCAL_MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Uninstall\\$CHROME_LONG_NAME": {
       "exists": "required",
       "values": {
         "UninstallString": {
           "type": "SZ",
-          "data": "\"$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\Installer\\setup.exe\" --uninstall --multi-install --chrome --system-level --verbose-logging"
+          "data": "\"$PROGRAM_FILES\\$CHROME_DIR\\Application\\$MINI_INSTALLER_FILE_VERSION\\Installer\\setup.exe\" --uninstall --system-level --verbose-logging"
         },
         "Version": {"type": "SZ", "data": "$MINI_INSTALLER_FILE_VERSION"}
       }
     },
     "HKEY_LOCAL_MACHINE\\Software\\Classes\\$CHROME_SHORT_NAME": {
       "exists": "forbidden"
     }
   }
 }