commit 2de5510bdfcb0e27814bb25adc1aa85c42fa09e0
author Charles Chen <charlesccchen@google.com> Tue Aug 11 16:43:17 2020 +0800
committer Charles Chen <charlesccchen@google.com> Mon Aug 24 16:30:48 2020 +0800
tree e869cd2839c45c2aa1df66a465567810931c6a8e
parent a437988c4239dd44986724e6a5b0508c3c4291cf

Fix lock contention in ResourcesManager

1. Scope dowm synchronized block to mAdjustedDisplays put and get
2. Use SoftReference instead of WeakReference because
   display's weak reference is cleared after getAdjustedDisplay
   returned and the cache didn't take effects previously.

fixes: 162445376
Test: ResourcesManagerPerfTest
Before:
    getDisplayMetrics_median: 3413
    getDisplayMetrics_mean: 3439
    getDisplayMetrics_min: 3364
    getDisplayMetrics_standardDeviation: 107
After:
    getDisplayMetrics_median: 3048
    getDisplayMetrics_mean: 3096
    getDisplayMetrics_min: 2999
    getDisplayMetrics_standardDeviation: 134

Change-Id: I8a5c3ba960c8231aee78b0e7fb958bf6845d5bb5