disable extension toolstrips by default, adding

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index bc23ce500f23a39d7785dc4e307760a850c285fe..fae9535b2c0a9cc260e79c590b18cec458a3efff 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -184,6 +184,9 @@ const char kEnableExperimentalWebGL[]       = "enable-webgl";
 // Enable experimental timeline API.
 const char kEnableExtensionTimelineApi[]    = "enable-extension-timeline-api";
 
+// Enable extension toolstrips (deprecated API - will be removed).
+const char kEnableExtensionToolstrips[]     = "enable-extension-toolstrips";
+
 // Enable the fastback page cache.
 const char kEnableFastback[]                = "enable-fastback";