Allow ADPF WorkDuration CPU duration to be zero

This patch updates the checks, tests, and documentation to ensure ADPF
CPU == 0 is allowed, and instead checks to make sure that both CPU
and GPU cannot be 0 at the same time.

Bug: 323226967
Test: atest PerformanceHintManagerTest
Change-Id: I6927899793c7d9801541465280af32627e200dc9

include/android/performance_hint.h

diff --git a/include/android/performance_hint.h b/include/android/performance_hint.h
index 08d339b..3c82d88 100644
--- a/include/android/performance_hint.h
+++ b/include/android/performance_hint.h
@@ -233,11 +233,11 @@
  * @param workDuration The {@link AWorkDuration} structure of times the thread group took to
  *     complete its last task in nanoseconds breaking down into different components.
  *
- *     The work period start timestamp, actual total duration and actual CPU duration must be
- *     positive.
+ *     The work period start timestamp and actual total duration must be greater than zero.
  *
- *     The actual GPU duration must be non-negative. If the actual GPU duration is 0, it means
- *     the actual GPU duration is not measured.
+ *     The actual CPU and GPU durations must be greater than or equal to zero, and at least one
+ *     of them must be greater than zero. When one of them is equal to zero, it means that type
+ *     of work was not measured for this workload.
  *
  * @return 0 on success.
  *         EINVAL if any duration is an invalid number.
@@ -289,7 +289,8 @@
  *
  * @param aWorkDuration The {@link AWorkDuration} created by calling {@link AWorkDuration_create()}
  * @param actualCpuDurationNanos The actual CPU work duration in nanoseconds. This number must be
- *        greater than zero.
+ *        greater than or equal to zero. If it is equal to zero, that means the CPU was not
+ *        measured.
  */
 void AWorkDuration_setActualCpuDurationNanos(AWorkDuration* _Nonnull aWorkDuration,
         int64_t actualCpuDurationNanos) __INTRODUCED_IN(__ANDROID_API_V__);
@@ -299,7 +300,7 @@
  *
  * @param aWorkDuration The {@link AWorkDuration} created by calling {@link AWorkDuration_create()}.
  * @param actualGpuDurationNanos The actual GPU work duration in nanoseconds, the number must be
- *        non-negative. If the actual GPU duration is 0, it means the actual GPU duration is
+ *        greater than or equal to zero. If it is equal to zero, that means the GPU was not
  *        measured.
  */
 void AWorkDuration_setActualGpuDurationNanos(AWorkDuration* _Nonnull aWorkDuration,