win: Add implementation of system_snapshot for Windows

compat/win/processor_power_information.h

Index: compat/win/processor_power_information.h
diff --git a/compat/win/sys/time.h b/compat/win/processor_power_information.h
similarity index 56%
copy from compat/win/sys/time.h
copy to compat/win/processor_power_information.h
index 46bdef2a3810669fcf310d9d8a29a29980c3c894..2ce8e04562675d917a03ba61ce2d8dd9e5873f48 100644
--- a/compat/win/sys/time.h
+++ b/compat/win/processor_power_information.h
@@ -12,12 +12,18 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#ifndef CRASHPAD_COMPAT_WIN_SYS_TIME_H_
-#define CRASHPAD_COMPAT_WIN_SYS_TIME_H_
+#ifndef CRASHPAD_COMPAT_WIN_PROCESSOR_POWER_INFORMATION_H_
+#define CRASHPAD_COMPAT_WIN_PROCESSOR_POWER_INFORMATION_H_
 
-struct timeval {
-  long tv_sec;
-  long tv_usec;
+// https://msdn.microsoft.com/en-us/library/windows/desktop/aa373184.aspx:
+// "Note that this structure definition was accidentally omitted from WinNT.h."
+struct PROCESSOR_POWER_INFORMATION {

[Mark Mentovai, 2015/02/27 22:27:42]

I thought that we could just put this into winnt.h and #include ../winnt.h,
since the doc says that the struct will show up in winnt.h in the future.

[scottmg, 2015/02/28 00:37:32]

Yeah, OK. I'm pretty skeptical that it'll ever get added, but I guess it's still
consistent with the docs.

+  ULONG Number;
+  ULONG MaxMhz;
+  ULONG CurrentMhz;
+  ULONG MhzLimit;
+  ULONG MaxIdleState;
+  ULONG CurrentIdleState;
 };
 
-#endif  // CRASHPAD_COMPAT_WIN_SYS_TIME_H_
+#endif  // CRASHPAD_COMPAT_WIN_PROCESSOR_POWER_INFORMATION_H_