Make it possible to run a test in sky_shell

sky/shell/linux/main.cc

Index: sky/shell/linux/main.cc
diff --git a/sky/shell/linux/main.cc b/sky/shell/linux/main.cc
index f6beeabe2d708995ed79105828bc36b44d8583a5..d04d290d0b3149c88f11875faa12f70f378d4500 100644
--- a/sky/shell/linux/main.cc
+++ b/sky/shell/linux/main.cc
@@ -16,6 +16,7 @@
 #include "sky/shell/shell.h"
 #include "sky/shell/shell_view.h"
 #include "sky/shell/switches.h"
+#include "sky/shell/testing/test_runner.h"
 
 namespace sky {
 namespace shell {
@@ -23,39 +24,26 @@ namespace {
 
 void Usage() {
   std::cerr << "Usage: sky_shell"
-            << " [MAIN_DART --" << switches::kPackageRoot << "=PACKAGE_ROOT]"
-            << " [--" << switches::kSnapshot << "=SNAPSHOT]" << std::endl;
+            << " --" << switches::kPackageRoot << "=PACKAGE_ROOT"
+            << " [ MAIN_DART ]" << std::endl;
 }
 
 void Init() {
   Shell::Init(make_scoped_ptr(new ServiceProviderContext(
       base::MessageLoop::current()->task_runner())));
 
-  // TODO(abarth): Currently we leak the ShellView.
-  ShellView* shell_view = new ShellView(Shell::Shared());
-
-  ViewportObserverPtr viewport_observer;
-  shell_view->view()->ConnectToViewportObserver(GetProxy(&viewport_observer));
-
   base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
 
-  if (command_line.HasSwitch(switches::kSnapshot)) {
-    std::string snapshot =
-        command_line.GetSwitchValueASCII(switches::kSnapshot);
-    viewport_observer->RunFromSnapshot(snapshot);
-    return;
-  }
+  std::string package_root =
+      command_line.GetSwitchValueASCII(switches::kPackageRoot);
 
-  if (command_line.HasSwitch(switches::kPackageRoot)) {
-    std::string main = command_line.GetArgs()[0];
-    std::string package_root =
-        command_line.GetSwitchValueASCII(switches::kPackageRoot);
-    viewport_observer->RunFromFile(main, package_root);
-    return;
-  }
+  std::string main;
+  auto args = command_line.GetArgs();
+  if (!args.empty())
+    main = args[0];
 
-  std::cerr << "One of --" << switches::kPackageRoot << " or --"
-            << switches::kSnapshot << " is required." << std::endl;
+  TestRunner::Shared().set_package_root(package_root);
+  TestRunner::Shared().Start(main);
 }
 
 }  // namespace
@@ -68,7 +56,8 @@ int main(int argc, const char* argv[]) {
 
   base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
 
-  if (command_line.HasSwitch(sky::shell::switches::kHelp)) {
+  if (command_line.HasSwitch(sky::shell::switches::kHelp) ||
+      !command_line.HasSwitch(sky::shell::switches::kPackageRoot)) {
     sky::shell::Usage();
     return 0;
   }