metrics/base: log whether drives have seek penalties.

components/metrics/proto/system_profile.proto

Index: components/metrics/proto/system_profile.proto
diff --git a/components/metrics/proto/system_profile.proto b/components/metrics/proto/system_profile.proto
index c73d8a95e8086a6bf9935297078e354ed3a48dd0..ef7a4ede843105d5bb2b0293b478995eb1e7cc80 100644
--- a/components/metrics/proto/system_profile.proto
+++ b/components/metrics/proto/system_profile.proto
@@ -92,7 +92,7 @@ message SystemProfileProto {
   }
   optional OS os = 5;
 
-  // Next tag for Hardware: 16
+  // Next tag for Hardware: 18
   // Information on the user's hardware.
   message Hardware {
     // The CPU architecture (x86, PowerPC, x86_64, ...)
@@ -261,6 +261,14 @@ message SystemProfileProto {
     // Lists vendor and product ids of external touchscreens.
     // Logged on ChromeOS only.
     repeated TouchScreen external_touchscreen = 15;
+
+    message Disk {

[Alexei Svitkine (slow), 2015/03/12 16:41:06]

Is Disk the right terminology here or should we use "Drive"? Not sure what the
difference is, just want to double check that we're using the more correct one -
whichever it is.

[Dan Beam, 2015/03/13 19:31:32]

I originally did this to avoid confusion with Google Drive.

I guess disk implies it spins.

s/disk/drive/g

+      optional bool has_seek_penalty = 1;
+    }
+    // The disk that Chrome loads from.

[Alexei Svitkine (slow), 2015/03/12 16:41:06]

Nit: "Chrome" -> "the application". (as this proto can be used by other products
potentially.

"loads" -> "was loaded"

Maybe even say "the application executable" to be clear about what this actually
means, since it's different than --user-data-dir below.

[Dan Beam, 2015/03/13 19:31:32]

Done.

+    optional Disk app_disk = 16;
+    // The disk that the current --user-data-dir loads from.
+    optional Disk user_data_disk = 17;
   }
   optional Hardware hardware = 6;