Kernel: Make the colonel run at "Idle" priority (the lowest possible.)

This means it won't hog the CPU for more than a single timeslice. :^)

Applications/ProcessManager/ProcessModel.cpp

@@ -84,12 +84,14 @@ GVariant ProcessModel::data(const GModelIndex& index, Role role) const
         case Column::State: return process.current_state.state;
         case Column::User: return process.current_state.user;
         case Column::Priority:
-            if (process.current_state.priority == "Low")
+            if (process.current_state.priority == "Idle")
                 return 0;
-            if (process.current_state.priority == "Normal")
+            if (process.current_state.priority == "Low")
                 return 1;
-            if (process.current_state.priority == "High")
+            if (process.current_state.priority == "Normal")
                 return 2;
+            if (process.current_state.priority == "High")
+                return 3;
             ASSERT_NOT_REACHED();
             return 3;
         case Column::Linear: return (int)process.current_state.linear;
@@ -110,6 +112,8 @@ GVariant ProcessModel::data(const GModelIndex& index, Role role) const
         case Column::State: return process.current_state.state;
         case Column::User: return process.current_state.user;
         case Column::Priority:
+            if (process.current_state.priority == "Idle")
+                return String::empty();
             if (process.current_state.priority == "High")
                 return *m_high_priority_icon;
             if (process.current_state.priority == "Low")

Kernel/Process.cpp

@@ -2376,6 +2376,7 @@ int Process::sys$get_shared_buffer_size(int shared_buffer_id)
 const char* to_string(Process::Priority priority)
 {
     switch (priority) {
+    case Process::IdlePriority: return "Idle";
     case Process::LowPriority: return "Low";
     case Process::NormalPriority: return "Normal";
     case Process::HighPriority: return "High";

Kernel/Process.h

@@ -43,6 +43,7 @@ public:
     static Vector<Process*> all_processes();
 
     enum Priority {
+        IdlePriority,
         LowPriority,
         NormalPriority,
         HighPriority,

Kernel/Scheduler.cpp

@@ -18,6 +18,8 @@ static dword time_slice_for(Process::Priority priority)
         return 15;
     case Process::LowPriority:
         return 5;
+    case Process::IdlePriority:
+        return 1;
     }
     ASSERT_NOT_REACHED();
 }
@@ -385,7 +387,7 @@ void Scheduler::initialize()
     initialize_redirection();
     s_colonel_process = Process::create_kernel_process("colonel", nullptr);
     // Make sure the colonel uses a smallish time slice.
-    s_colonel_process->set_priority(Process::LowPriority);
+    s_colonel_process->set_priority(Process::IdlePriority);
     load_task_register(s_redirection.selector);
 }