Updating documentation

ppapi/c/pp_time.h

Index: ppapi/c/pp_time.h
===================================================================
--- ppapi/c/pp_time.h	(revision 73626)
+++ ppapi/c/pp_time.h	(working copy)
@@ -7,7 +7,7 @@
 
 /**
  * @file
- * Defines the API ...
+ * This file defines time and time ticks types.
  */
 
 #include "ppapi/c/pp_macros.h"
@@ -17,9 +17,9 @@
  * @{
  */
 /**
- * PP_Time represents the "wall clock time" according to the browser and is
- * defined as the number of seconds since the Epoch (00:00:00 UTC, January 1,
- * 1970).
+ * The PP_Time type represents the "wall clock time" according to the browser
+ * and is defined as the number of seconds since the Epoch (00:00:00 UTC,
+ * January 1, 1970).
  */
 typedef double PP_Time;
 PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_Time, 8);
@@ -32,10 +32,11 @@
  * @{
  */
 /**
- * Represents time ticks which is measured in seconds and is used for indicating
- * the time that certain messages were received. In contrast to PP_Time, it
- * does not correspond to any actual wall clock time and will not change
- * discontinuously if the user changes their computer clock.
+ * A PP_TimeTicks value represents time ticks which are measured in seconds
+ * and are used for indicating the time that certain messages were received.
+ * In contrast to PP_Time, PP_TimeTicks does not correspond to any actual
+ * wall clock time and will not change discontinuously if the user changes
+ * their computer clock.
  *
  * The units are in seconds, but are not measured relative to any particular
  * epoch, so the most you can do is compare two values.