Linux: refactor zygote support

http://code.google.com/p/chromium/wiki/LinuxZygote

  * Move Chrome specific bits out of base
  * Move away from the idea of reserved file descriptors (which don't really work
  with zygotes)
  * Load resources before forking renderers (means that we don't need
  communication between the zygote process and the renderers)
  * Make sure that gdb works against the browser again
  * Make sure that we have different ASLR between the renderers and the browser.

http://codereview.chromium.org/119335

(This is a reland. First landed in r18109, reverted in r18112.)


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18291 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: cc8f146d34a3b13cd80d8b3530fd76445774b1c6
diff --git a/base/file_util_posix.cc b/base/file_util_posix.cc
index 92b9d00..aca0ff9 100644
--- a/base/file_util_posix.cc
+++ b/base/file_util_posix.cc
@@ -27,7 +27,6 @@
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "base/time.h"
-#include "base/zygote_manager.h"
 
 namespace file_util {
 
@@ -646,19 +645,8 @@
 }
 
 bool MemoryMappedFile::MapFileToMemory(const FilePath& file_name) {
-  file_ = -1;
-#if defined(OS_LINUX)
-  base::ZygoteManager* zm = base::ZygoteManager::Get();
-  if (zm) {
-    file_ = zm->OpenFile(file_name.value().c_str());
-    if (file_ == -1) {
-      LOG(INFO) << "Zygote manager can't open " << file_name.value()
-                << ", retrying locally.  (OK at start of ui_tests.)";
-    }
-  }
-#endif  // defined(OS_LINUX)
-  if (file_ == -1)
-    file_ = open(file_name.value().c_str(), O_RDONLY);
+  file_ = open(file_name.value().c_str(), O_RDONLY);
+
   if (file_ == -1) {
     LOG(ERROR) << "Couldn't open " << file_name.value();
     return false;