Refactor SetOmahaExperimentLabel out of gcpai and into install_util.

chrome/installer/util/browser_distribution.h

Index: chrome/installer/util/browser_distribution.h
diff --git a/chrome/installer/util/browser_distribution.h b/chrome/installer/util/browser_distribution.h
index 8525a9de3477155b6f5589aa1c3b349ce017afc6..9b01f7b6f507edf14e3c22595c9a52120c8d5731 100644
--- a/chrome/installer/util/browser_distribution.h
+++ b/chrome/installer/util/browser_distribution.h
@@ -164,6 +164,10 @@ class BrowserDistribution {
       const installer::Product& installation,
       const FilePath& application_path);
 
+  // Returns true if this distribution should set the Omaha experiment_labels
+  // registry value.
+  virtual bool ShouldSetExperimentLabels();
+
  protected:
   explicit BrowserDistribution(Type type);