Use file thread when converting paths to absolute when loading apps.

apps/launcher.cc

Index: apps/launcher.cc
diff --git a/apps/launcher.cc b/apps/launcher.cc
index 8d31a0115c46e671d56a953aa194942a20f388df..e081eb185f131589133144d3a6fa50d822c4ea9e 100644
--- a/apps/launcher.cc
+++ b/apps/launcher.cc
@@ -63,8 +63,8 @@ namespace {
 
 const char kFallbackMimeType[] = "application/octet-stream";
 
-bool MakePathAbsolute(const base::FilePath& current_directory,
-                      base::FilePath* file_path) {
+bool DoMakePathAbsolute(const base::FilePath& current_directory,
+                        base::FilePath* file_path) {
   DCHECK(file_path);
   if (file_path->IsAbsolute())
     return true;
@@ -81,27 +81,11 @@ bool MakePathAbsolute(const base::FilePath& current_directory,
   return true;
 }
 
-bool GetAbsolutePathFromCommandLine(const CommandLine& command_line,
-                                    const base::FilePath& current_directory,
-                                    base::FilePath* path) {
-  if (!command_line.GetArgs().size())
-    return false;
-
-  base::FilePath relative_path(command_line.GetArgs()[0]);
-  base::FilePath absolute_path(relative_path);
-  if (!MakePathAbsolute(current_directory, &absolute_path)) {
-    LOG(WARNING) << "Cannot make absolute path from " << relative_path.value();
-    return false;
-  }
-  *path = absolute_path;
-  return true;
-}
-
 // Helper method to launch the platform app |extension| with no data. This
 // should be called in the fallback case, where it has been impossible to
 // load or obtain file launch data.
 void LaunchPlatformAppWithNoData(Profile* profile, const Extension* extension) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
   AppEventRouter::DispatchOnLaunchedEvent(profile, extension);
 }
 
@@ -119,7 +103,7 @@ class PlatformAppPathLauncher
       : profile_(profile), extension_(extension), file_path_(file_path) {}
 
   void Launch() {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    DCHECK_CURRENTLY_ON(BrowserThread::UI);
     if (file_path_.empty()) {
       LaunchPlatformAppWithNoData(profile_, extension_);
       return;
@@ -147,11 +131,33 @@ class PlatformAppPathLauncher
     Launch();
   }
 
+  void LaunchWithRelativePath(const base::FilePath& current_directory) {
+    BrowserThread::PostTask(
+        BrowserThread::FILE,
+        FROM_HERE,
+        base::Bind(&PlatformAppPathLauncher::MakePathAbsolute,
+                   this,
+                   current_directory));
+  }
+
  private:
   friend class base::RefCountedThreadSafe<PlatformAppPathLauncher>;
 
   virtual ~PlatformAppPathLauncher() {}
 
+  void MakePathAbsolute(const base::FilePath& current_directory) {
+    DCHECK_CURRENTLY_ON(BrowserThread::FILE);
+
+    if (!DoMakePathAbsolute(current_directory, &file_path_)) {
+      LOG(WARNING) << "Cannot make absolute path from " << file_path_.value();
+      file_path_ = base::FilePath();
+    }
+
+    BrowserThread::PostTask(BrowserThread::UI,
+                            FROM_HERE,
+                            base::Bind(&PlatformAppPathLauncher::Launch, this));
+  }
+
   void OnFileValid() {
 #if defined(OS_CHROMEOS)
     if (drive::util::IsUnderDriveMountPoint(file_path_)) {
@@ -171,7 +177,7 @@ class PlatformAppPathLauncher
   }
 
   void GetMimeTypeAndLaunch() {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
+    DCHECK_CURRENTLY_ON(BrowserThread::FILE);
 
     // If the file doesn't exist, or is a directory, launch with no launch data.
     if (!base::PathExists(file_path_) ||
@@ -205,7 +211,7 @@ class PlatformAppPathLauncher
 
 #if defined(OS_CHROMEOS)
   void GetMimeTypeAndLaunchForDriveFile() {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
     drive::FileSystemInterface* file_system =
         drive::util::GetFileSystemByProfile(profile_);
@@ -222,7 +228,7 @@ class PlatformAppPathLauncher
   void OnGotDriveFile(drive::FileError error,
                       const base::FilePath& file_path,
                       scoped_ptr<drive::ResourceEntry> entry) {
-    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+    DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
     if (error != drive::FILE_ERROR_OK ||
         !entry || entry->file_specific_info().is_hosted_document()) {
@@ -310,9 +316,12 @@ class PlatformAppPathLauncher
   // The profile the app should be run in.
   Profile* profile_;
   // The extension providing the app.
+  // TODO(benwells): Hold onto the extension ID instead of a pointer as it
+  // is possible the extension will be unloaded while we're doing our thing.
+  // See http://crbug.com/372270 for details.
   const Extension* extension_;
   // The path to be passed through to the app.
-  const base::FilePath file_path_;
+  base::FilePath file_path_;
   // The ID of the file handler used to launch the app.
   std::string handler_id_;
 
@@ -342,22 +351,20 @@ void LaunchPlatformAppWithCommandLine(Profile* profile,
     }
   }
 
-  base::FilePath path;
-  if (!GetAbsolutePathFromCommandLine(command_line, current_directory, &path)) {
+  if (command_line.GetArgs().empty()) {
     LaunchPlatformAppWithNoData(profile, extension);
     return;
   }
 
-  // TODO(benwells): add a command-line argument to provide a handler ID.
-  LaunchPlatformAppWithPath(profile, extension, path);
+  base::FilePath file_path(command_line.GetArgs()[0]);
+  scoped_refptr<PlatformAppPathLauncher> launcher =
+      new PlatformAppPathLauncher(profile, extension, file_path);
+  launcher->LaunchWithRelativePath(current_directory);
 }
 
 void LaunchPlatformAppWithPath(Profile* profile,
                                const Extension* extension,
                                const base::FilePath& file_path) {
-  // launcher will be freed when nothing has a reference to it. The message
-  // queue will retain a reference for any outstanding task, so when the
-  // launcher has finished it will be freed.
   scoped_refptr<PlatformAppPathLauncher> launcher =
       new PlatformAppPathLauncher(profile, extension, file_path);
   launcher->Launch();