Move launcher_.reset() from UITestBase constructor to SetUp().

chrome/test/automation/automation_proxy_uitest.cc

Index: chrome/test/automation/automation_proxy_uitest.cc
diff --git a/chrome/test/automation/automation_proxy_uitest.cc b/chrome/test/automation/automation_proxy_uitest.cc
index 60830e038184151a5461bd8a0415b94f6dcfc369..77eb5a28d0a25dcd30976e7c255c4ef4be757313 100644
--- a/chrome/test/automation/automation_proxy_uitest.cc
+++ b/chrome/test/automation/automation_proxy_uitest.cc
@@ -887,9 +887,7 @@ template <typename T> T** ReceivePointer(scoped_refptr<T>& p) {  // NOLINT
   return reinterpret_cast<T**>(&p);
 }
 
-ExternalTabUITest::ExternalTabUITest() : UITest(MessageLoop::TYPE_UI) {
-  launcher_.reset(CreateProxyLauncher());
-}
+ExternalTabUITest::ExternalTabUITest() : UITest(MessageLoop::TYPE_UI) {}
 
 // Replace the default automation proxy with our mock client.
 ProxyLauncher* ExternalTabUITest::CreateProxyLauncher() {