Add process start time and CPU time columns to task manager

chrome/browser/task_manager/sampling/shared_sampler.h

Index: chrome/browser/task_manager/sampling/shared_sampler.h
diff --git a/chrome/browser/task_manager/sampling/shared_sampler.h b/chrome/browser/task_manager/sampling/shared_sampler.h
index def063488db11eaf4a92a8351dc611ab9a92e96e..2132ec40198fd5a1c839ee52172ca465741ba85d 100644
--- a/chrome/browser/task_manager/sampling/shared_sampler.h
+++ b/chrome/browser/task_manager/sampling/shared_sampler.h
@@ -41,6 +41,8 @@ class SharedSampler : public base::RefCountedThreadSafe<SharedSampler> {
   // These callbacks are passed via RegisterCallbacks.
   using OnIdleWakeupsCallback = base::Callback<void(int)>;
   using OnPhysicalMemoryCallback = base::Callback<void(int64_t)>;
+  using OnStartTimeCallback = base::Callback<void(uint64_t)>;
+  using OnCpuTimeCallback = base::Callback<void(uint64_t)>;
 
   // Returns a combination of refresh flags supported by the shared sampler.
   int64_t GetSupportedFlags() const;
@@ -48,7 +50,9 @@ class SharedSampler : public base::RefCountedThreadSafe<SharedSampler> {
   // Registers task group specific callbacks.
   void RegisterCallbacks(base::ProcessId process_id,
                          const OnIdleWakeupsCallback& on_idle_wakeups,
-                         const OnPhysicalMemoryCallback& on_physical_memory);
+                         const OnPhysicalMemoryCallback& on_physical_memory,
+                         const OnStartTimeCallback& on_start_time,
+                         const OnCpuTimeCallback& on_cpu_time);

[stanisc, 2016/12/21 19:17:52]

If we add any more callbacks we should consider replacing all this with a struct
and pass a struct instead.

Actually there is already a struct 'Callbacks' defined in .cc file. May be we
should expose it here.

[chengx, 2016/12/21 22:05:54]

If I use 'Callbacks' for RegisterCallbacks() in shared_sampler_win.cc, I need to
use it for RegisterCallbacks() in shared_sampler_posix.cc as well. However,
'Callbacks' is only defined in OS_WIN as in the header file. Can I safely remove
if if_def(OS_WIN) in the header file?

 
   // Unregisters task group specific callbacks.
   void UnregisterCallbacks(base::ProcessId process_id);
@@ -71,6 +75,8 @@ class SharedSampler : public base::RefCountedThreadSafe<SharedSampler> {
 
     OnIdleWakeupsCallback on_idle_wakeups;
     OnPhysicalMemoryCallback on_physical_memory;
+    OnStartTimeCallback on_start_time;
+    OnCpuTimeCallback on_cpu_time;
 
    private:
     DISALLOW_COPY_AND_ASSIGN(Callbacks);
@@ -83,6 +89,8 @@ class SharedSampler : public base::RefCountedThreadSafe<SharedSampler> {
     base::ProcessId process_id;
     int idle_wakeups_per_second;
     int64_t physical_bytes;
+    uint64_t start_time;  // in unit of 100 ns

[brucedawson, 2016/12/21 02:13:40]

Should probably be "In units of 100 ns" (capitalization and pluralize 'units')

Or "Units of 100 ns"

[chengx, 2016/12/21 22:05:54]

Done.

+    uint64_t cpu_time;    // in unit of 100 ns
   };
 
   typedef std::vector<RefreshResult> RefreshResults;