[Chromoting] Reimplemented the worker process launcher to take into account the encountered issues:

remoting/host/win/launch_process_with_token.cc

Index: remoting/host/win/launch_process_with_token.cc
diff --git a/remoting/host/win/launch_process_with_token.cc b/remoting/host/win/launch_process_with_token.cc
index 1320e2a3dd911fa932d1c3fafc93f62109e045f1..c531ff967c3a6850a84a6d5ff2b5a193d616cf3b 100644
--- a/remoting/host/win/launch_process_with_token.cc
+++ b/remoting/host/win/launch_process_with_token.cc
@@ -32,11 +32,6 @@ const WINSTATIONINFOCLASS kCreateProcessPipeNameClass =
 const int kPipeBusyWaitTimeoutMs = 2000;
 const int kPipeConnectMaxAttempts = 3;
 
-// The minimum and maximum delays between attempts to inject host process into
-// a session.
-const int kMaxLaunchDelaySeconds = 60;
-const int kMinLaunchDelaySeconds = 1;
-
 // Name of the default session desktop.
 const char kDefaultDesktopName[] = "winsta0\\default";
 
@@ -292,6 +287,32 @@ bool CreateRemoteSessionProcess(
                               << response.process_information.dwProcessId;
       return false;
     }
+
+    // N.B. THREAD_ALL_ACCESS is different in XP and Vista+ versions of
+    // the SDK. |desired_access| below is effectively THREAD_ALL_ACCESS from
+    // the XP version of the SDK.
+    desired_access =
+        STANDARD_RIGHTS_REQUIRED |
+        SYNCHRONIZE |
+        THREAD_TERMINATE |
+        THREAD_SUSPEND_RESUME |
+        THREAD_GET_CONTEXT |
+        THREAD_SET_CONTEXT |
+        THREAD_QUERY_INFORMATION |
+        THREAD_SET_INFORMATION |
+        THREAD_SET_THREAD_TOKEN |
+        THREAD_IMPERSONATE |
+        THREAD_DIRECT_IMPERSONATION;
+    response.process_information.hThread =
+        OpenThread(desired_access,
+                   FALSE,
+                   response.process_information.dwThreadId);
+    if (!response.process_information.hThread) {
+      LOG_GETLASTERROR(ERROR) << "Failed to open thread "
+                              << response.process_information.dwThreadId;
+      CloseHandle(response.process_information.hProcess);
+      return false;
+    }
   }
 
   *process_information_out = response.process_information;