chrome: Add support for custom crosh command.

This adds the "--crosh-command" command line switch that
cab be used to specify an alternative crosh command.

BUG=677267
TEST=chrome --crosh-command=/bin/bash

Review-Url: https://codereview.chromium.org/2579833005
Cr-Commit-Position: refs/heads/master@{#442767}

chrome/browser/extensions/api/terminal/terminal_private_api.cc

@@ -7,6 +7,7 @@
 #include <utility>
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/json/json_writer.h"
 #include "base/memory/ptr_util.h"
 #include "base/sys_info.h"
@@ -14,6 +15,7 @@
 #include "chrome/browser/extensions/api/terminal/terminal_extension_helper.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_tab_util.h"
+#include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/api/terminal_private.h"
 #include "chromeos/process_proxy/process_proxy_registry.h"
 #include "content/public/browser/browser_context.h"
@@ -40,18 +42,22 @@ const char kCroshCommand[] = "/usr/bin/crosh";
 // We make stubbed crosh just echo back input.
 const char kStubbedCroshCommand[] = "cat";
 
-const char* GetCroshPath() {
+std::string GetCroshPath() {
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  if (command_line->HasSwitch(switches::kCroshCommand))
+    return command_line->GetSwitchValueASCII(switches::kCroshCommand);
+
   if (base::SysInfo::IsRunningOnChromeOS())
-    return kCroshCommand;
-  else
-    return kStubbedCroshCommand;
+    return std::string(kCroshCommand);
+
+  return std::string(kStubbedCroshCommand);
 }
 
-const char* GetProcessCommandForName(const std::string& name) {
+std::string GetProcessCommandForName(const std::string& name) {
   if (name == kCroshName)
     return GetCroshPath();
   else
-    return NULL;
+    return std::string();
 }
 
 void NotifyProcessOutput(content::BrowserContext* browser_context,
@@ -101,7 +107,7 @@ int GetTabOrWindowSessionId(content::BrowserContext* browser_context,
 namespace extensions {
 
 TerminalPrivateOpenTerminalProcessFunction::
-    TerminalPrivateOpenTerminalProcessFunction() : command_(NULL) {}
+    TerminalPrivateOpenTerminalProcessFunction() {}
 
 TerminalPrivateOpenTerminalProcessFunction::
     ~TerminalPrivateOpenTerminalProcessFunction() {}
@@ -113,7 +119,7 @@ TerminalPrivateOpenTerminalProcessFunction::Run() {
   EXTENSION_FUNCTION_VALIDATE(params.get());
 
   command_ = GetProcessCommandForName(params->process_name);
-  if (!command_)
+  if (command_.empty())
     return RespondNow(Error("Invalid process name."));
 
   content::WebContents* caller_contents = GetSenderWebContents();
@@ -150,12 +156,12 @@ TerminalPrivateOpenTerminalProcessFunction::Run() {
 void TerminalPrivateOpenTerminalProcessFunction::OpenOnFileThread(
     const ProcessOutputCallback& output_callback,
     const OpenProcessCallback& callback) {
-  DCHECK(command_);
+  DCHECK(!command_.empty());
 
   chromeos::ProcessProxyRegistry* registry =
       chromeos::ProcessProxyRegistry::Get();
 
-  int terminal_id = registry->OpenProcess(command_, output_callback);
+  int terminal_id = registry->OpenProcess(command_.c_str(), output_callback);
 
   content::BrowserThread::PostTask(content::BrowserThread::UI, FROM_HERE,
                                    base::Bind(callback, terminal_id));

chrome/browser/extensions/api/terminal/terminal_private_api.h

@@ -36,7 +36,7 @@ class TerminalPrivateOpenTerminalProcessFunction
                         const OpenProcessCallback& callback);
   void RespondOnUIThread(int terminal_id);
 
-  const char* command_;
+  std::string command_;
 };
 
 // Send input to the terminal process specified by the terminal ID, which is set

chrome/common/chrome_switches.cc

@@ -977,6 +977,9 @@ const char kWebApkServerUrl[] = "webapk-server-url";
 #if defined(OS_CHROMEOS)
 // Enables native cups integration
 const char kEnableNativeCups[] = "enable-native-cups";
+
+// Custom crosh command.
+const char kCroshCommand[] = "crosh-command";
 #endif  // defined(OS_CHROMEOS)
 
 #if defined(USE_ASH)

chrome/common/chrome_switches.h

@@ -288,6 +288,7 @@ extern const char kWebApkServerUrl[];
 
 #if defined(OS_CHROMEOS)
 extern const char kEnableNativeCups[];
+extern const char kCroshCommand[];
 #endif  // defined(OS_CHROMEOS)
 
 #if defined(USE_ASH)