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..8c0b53b85049bbf45f89a6a95618ec82c4cfb137 100644
--- a/chrome/test/automation/automation_proxy_uitest.cc
+++ b/chrome/test/automation/automation_proxy_uitest.cc
@@ -887,10 +887,6 @@ template <typename T> T** ReceivePointer(scoped_refptr<T>& p) {  // NOLINT
   return reinterpret_cast<T**>(&p);
 }
 
-ExternalTabUITest::ExternalTabUITest() : UITest(MessageLoop::TYPE_UI) {
-  launcher_.reset(CreateProxyLauncher());
-}
-
 // Replace the default automation proxy with our mock client.
 ProxyLauncher* ExternalTabUITest::CreateProxyLauncher() {
   return new ExternalTabUITestMockLauncher(&mock_);