Uninstall multi-install Chrome Frame when updated.

chrome/installer/util/util_constants.h

Index: chrome/installer/util/util_constants.h
diff --git a/chrome/installer/util/util_constants.h b/chrome/installer/util/util_constants.h
index 5a1ec0a036d141720813ebff1611923a944aef75..ad9992331bb03d32005481439a29d45c477aaff4 100644
--- a/chrome/installer/util/util_constants.h
+++ b/chrome/installer/util/util_constants.h
@@ -127,12 +127,14 @@ enum InstallerStage {
   CONFIGURE_AUTO_LAUNCH,       // 16: Configuring Chrome to auto-launch.
   CREATING_VISUAL_MANIFEST,    // 17: Creating VisualElementsManifest.xml
   DEFERRING_TO_HIGHER_VERSION,  // 18: Deferring to an installed higher version.
-  NUM_STAGES                   // 19: The number of stages.
+  UNINSTALLING_BINARIES,       // 19: Uninstalling unused binaries.
+  UNINSTALLING_CHROME_FRAME,   // 20: Uninstalling multi-install Chrome Frame.
+  NUM_STAGES                   // 21: The number of stages.
 };
 
 // When we start reporting the numerical values from the enum, the order
 // above MUST be preserved.
-COMPILE_ASSERT(DEFERRING_TO_HIGHER_VERSION == 18,
+COMPILE_ASSERT(UNINSTALLING_CHROME_FRAME == 20,
                never_ever_ever_change_InstallerStage_values_bang);
 
 namespace switches {