fix uninitialization issue in JankTracker

We should initialize mSwapDeadline in JankTracker, or it can be a very
large randomized value and then makes jank tracker not collect concrete
jank type of frames appropriately as expected.

Bug: 161656795
Test: run cts -m CtsIncidentHostTestCases -t
   com.android.server.cts.GraphicsStatsValidationTest#testJankyDrawFrame
Change-Id: I057a50a74502918619204f9164f6a954f8e9c5de
diff --git a/libs/hwui/JankTracker.cpp b/libs/hwui/JankTracker.cpp
index d25fc4b..b2c39c9 100644
--- a/libs/hwui/JankTracker.cpp
+++ b/libs/hwui/JankTracker.cpp
@@ -139,6 +139,9 @@
         (*mGlobalData)->reportJank();
     }
 
+    if (mSwapDeadline < 0) {
+        mSwapDeadline = frame[FrameInfoIndex::IntendedVsync] + mFrameInterval;
+    }
     bool isTripleBuffered = (mSwapDeadline - frame[FrameInfoIndex::IntendedVsync]) > (mFrameInterval * 0.1);
 
     mSwapDeadline = std::max(mSwapDeadline + mFrameInterval,