SoftHevcDec: notify error for fatal errors in decoder

Bug: 129796771
Bug: 130578045
Test: adb shell stagefright -s -S /sdcard/crowd422_hevc.mp4
Test: Ensure decoder doesn't attemp decoding all frames
Test: atest android.media.cts.DecoderTest
Test: android.media.cts.AdaptivePlaybackTest

Change-Id: Icb183d9aaa4280416c468e71cf319dacacf3b2ea