modules/video_coding refactorings

The main purpose was the interface-> include rename, but other files
were also moved, eliminating the "main" dir.

To avoid breaking downstream, the "interface" directories were copied
into a new "video_coding/include" dir. The old headers got pragma
warnings added about deprecation (a very short deprecation since I plan
to remove them as soon downstream is updated).

Other files also moved:
video_coding/main/source -> video_coding
video_coding/main/test -> video_coding/test

BUG=webrtc:5095
TESTED=Passing compile-trybots with --clobber flag:
git cl try --clobber --bot=win_compile_rel --bot=linux_compile_rel --bot=android_compile_rel --bot=mac_compile_rel --bot=ios_rel --bot=linux_gn_rel --bot=win_x64_gn_rel --bot=mac_x64_gn_rel --bot=android_gn_rel -m tryserver.webrtc

R=stefan@webrtc.org, tommi@webrtc.org

Review URL: https://codereview.webrtc.org/1417283007 .

Cr-Commit-Position: refs/heads/master@{#10694}

webrtc/modules/video_coding/codec_timer.h

@@ -0,0 +1,61 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef WEBRTC_MODULES_VIDEO_CODING_CODEC_TIMER_H_
+#define WEBRTC_MODULES_VIDEO_CODING_CODEC_TIMER_H_
+
+#include "webrtc/modules/include/module_common_types.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();
+
+    // Updates the max filtered decode time.
+    void MaxFilter(int32_t newDecodeTimeMs, int64_t nowMs);
+
+    // Empty the list of timers.
+    void Reset();
+
+    // Get the required decode time in ms.
+    int32_t RequiredDecodeTimeMs(FrameType frameType) const;
+
+private:
+    void UpdateMaxHistory(int32_t decodeTime, int64_t now);
+    void ProcessHistory(int64_t nowMs);
+
+    int32_t                     _filteredMax;
+    // The number of samples ignored so far.
+    int32_t                     _ignoredSampleCount;
+    int32_t                     _shortMax;
+    VCMShortMaxSample           _history[MAX_HISTORY_SIZE];
+
+};
+
+}  // namespace webrtc
+
+#endif // WEBRTC_MODULES_VIDEO_CODING_CODEC_TIMER_H_