Initial checkin of the out of process worker implementation....

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
===================================================================
--- chrome/common/chrome_switches.cc	(revision 10842)
+++ chrome/common/chrome_switches.cc	(working copy)
@@ -74,9 +74,12 @@
 // Path to the exe to run for the renderer subprocess
 const wchar_t kRendererPath[]                  = L"renderer-path";
 
-// Causes the process to run as plugin host
+// Causes the process to run as a plugin subprocess.
 const wchar_t kPluginProcess[]                 = L"plugin";
 
+// Causes the process to run as a worker subprocess.
+const wchar_t kWorkerProcess[]                 = L"worker";
+
 // Runs the renderer and plugins in the same process as the browser
 const wchar_t kSingleProcess[]                 = L"single-process";