Revert of VCMCodecTimer: Change filter from max to 95th percentile (patchset #5 id:180001 of https://codereview.webrtc.org/1742323002/ )

Reason for revert:
Caused unexpected perf stats changes, see http://crbug/594575.

Original issue's description:
> VCMCodecTimer: Change filter from max to 95th percentile
>
> The purpose with this change is to make the filter more robust against anomalies. googMaxDecodeMs is expected to drop a litte by this.
>
> BUG=b/27306053
>
> Committed: https://crrev.com/4bf0c717740d1834e810ea5f32b3c4306c64235f
> Cr-Commit-Position: refs/heads/master@{#11952}

TBR=stefan@webrtc.org,philipel@webrtc.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=594575,b/27306053

Review URL: https://codereview.webrtc.org/1808693002

Cr-Commit-Position: refs/heads/master@{#12018}
diff --git a/webrtc/modules/video_coding/codec_timer.h b/webrtc/modules/video_coding/codec_timer.h
index 90ef6bb..8ebd82a 100644
--- a/webrtc/modules/video_coding/codec_timer.h
+++ b/webrtc/modules/video_coding/codec_timer.h
@@ -11,39 +11,45 @@
 #ifndef WEBRTC_MODULES_VIDEO_CODING_CODEC_TIMER_H_
 #define WEBRTC_MODULES_VIDEO_CODING_CODEC_TIMER_H_
 
-#include <queue>
-
 #include "webrtc/modules/include/module_common_types.h"
-#include "webrtc/modules/video_coding/percentile_filter.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
 
+// MAX_HISTORY_SIZE * SHORT_FILTER_MS defines the window size in milliseconds
+#define MAX_HISTORY_SIZE 10
+#define SHORT_FILTER_MS 1000
+
+class VCMShortMaxSample {
+ public:
+  VCMShortMaxSample() : shortMax(0), timeMs(-1) {}
+
+  int32_t shortMax;
+  int64_t timeMs;
+};
+
 class VCMCodecTimer {
  public:
   VCMCodecTimer();
 
-  // Add a new decode time to the filter.
-  void AddTiming(int64_t new_decode_time_ms, int64_t now_ms);
+  // Updates the max filtered decode time.
+  void MaxFilter(int32_t newDecodeTimeMs, int64_t nowMs);
 
-  // Get the required decode time in ms. It is the 95th percentile observed
-  // decode time within a time window.
-  int64_t RequiredDecodeTimeMs() const;
+  // Empty the list of timers.
+  void Reset();
+
+  // Get the required decode time in ms.
+  int32_t RequiredDecodeTimeMs(FrameType frameType) const;
 
  private:
-  struct Sample {
-    Sample(int64_t decode_time_ms, int64_t sample_time_ms);
-    int64_t decode_time_ms;
-    int64_t sample_time_ms;
-  };
+  void UpdateMaxHistory(int32_t decodeTime, int64_t now);
+  void ProcessHistory(int64_t nowMs);
 
+  int32_t _filteredMax;
   // The number of samples ignored so far.
-  int ignored_sample_count_;
-  // Queue with history of latest decode time values.
-  std::queue<Sample> history_;
-  // |filter_| contains the same values as |history_|, but in a data structure
-  // that allows efficient retrieval of the percentile value.
-  PercentileFilter filter_;
+  int32_t _ignoredSampleCount;
+  int32_t _shortMax;
+  VCMShortMaxSample _history[MAX_HISTORY_SIZE];
 };
 
 }  // namespace webrtc