Changes pulled data to use Parcel objects.

Previously, pulled data was returned as a string. We instead
return the data as an array of StatsLogEventWrapper, which encodes
using the binary-encoded format liblog uses. StatsD uses the same
parsing as for pushed events to convert these. This CL also fixes
the parsing of log_msg since the strings were previously emptied
before we had a chance to read the values.

Note that the cpp-aidl can't support List of Parcelable, so we
have to return the results as an array.

Test: Manual using the new command in StatsService to print results.
Also created a new unit-test by creating a dummy pull code of -1,
but this test is deleted since it required creating a fake output in
StatsCompanionService.

Change-Id: I1cfb9ea081a59292a60e934e8527adc40982ed80
diff --git a/cmds/statsd/src/external/KernelWakelockPuller.cpp b/cmds/statsd/src/external/KernelWakelockPuller.cpp
index b9abee0..ee072f8 100644
--- a/cmds/statsd/src/external/KernelWakelockPuller.cpp
+++ b/cmds/statsd/src/external/KernelWakelockPuller.cpp
@@ -37,9 +37,9 @@
 
 // The reading and parsing are implemented in Java. It is not difficult to port over. But for now
 // let StatsCompanionService handle that and send the data back.
-String16 KernelWakelockPuller::pull() {
+vector<StatsLogEventWrapper> KernelWakelockPuller::pull() {
     sp<IStatsCompanionService> statsCompanion = StatsService::getStatsCompanionService();
-    String16 returned_value("");
+    vector<StatsLogEventWrapper> returned_value;
     if (statsCompanion != NULL) {
         Status status = statsCompanion->pullData(KernelWakelockPuller::PULL_CODE_KERNEL_WAKELOCKS,
                                                  &returned_value);
@@ -47,12 +47,10 @@
             ALOGW("error pulling kernel wakelock");
         }
         ALOGD("KernelWakelockPuller::pull succeeded!");
-        // TODO: remove this when we integrate into aggregation chain.
-        ALOGD("%s", String8(returned_value).string());
         return returned_value;
     } else {
         ALOGW("statsCompanion not found!");
-        return String16();
+        return returned_value;
     }
 }