Renamed RTCStatsReport to RTCLegacyStatsReport in objc files.

This is to avoid a naming conflict with webrtc::RTCStatsReport that is
surfaced if you try to include it in peerconnectioninterface.h.

Background: The current stats is very much non-spec-compliant. A new
stats collection API is underway that is meant to be spec-compliant.
Some classes in Chromium and webrtc/sdk/objc have spec-compliant names
but non-spec-compliant behavior. These are being renamed to "Legacy" so
that new spec-compliant classes can be added with the correct names.

BUG=chromium:627816
TBR=tkchin@webrtc.org
NOTRY=True

Review-Url: https://codereview.webrtc.org/2313943002
Cr-Commit-Position: refs/heads/master@{#14150}

webrtc/sdk/objc/Framework/Classes/RTCLegacyStatsReport.mm

@@ -0,0 +1,60 @@
+/*
+ *  Copyright 2015 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.
+ */
+
+#import "RTCLegacyStatsReport+Private.h"
+
+#import "NSString+StdString.h"
+#import "WebRTC/RTCLogging.h"
+
+#include "webrtc/base/checks.h"
+
+@implementation RTCLegacyStatsReport
+
+@synthesize timestamp = _timestamp;
+@synthesize type = _type;
+@synthesize reportId = _reportId;
+@synthesize values = _values;
+
+- (NSString *)description {
+  return [NSString stringWithFormat:@"RTCLegacyStatsReport:\n%@\n%@\n%f\n%@",
+                                    _reportId,
+                                    _type,
+                                    _timestamp,
+                                    _values];
+}
+
+#pragma mark - Private
+
+- (instancetype)initWithNativeReport:(const webrtc::StatsReport &)nativeReport {
+  if (self = [super init]) {
+    _timestamp = nativeReport.timestamp();
+    _type = [NSString stringForStdString:nativeReport.TypeToString()];
+    _reportId = [NSString stringForStdString:
+        nativeReport.id()->ToString()];
+
+    NSUInteger capacity = nativeReport.values().size();
+    NSMutableDictionary *values =
+        [NSMutableDictionary dictionaryWithCapacity:capacity];
+    for (auto const &valuePair : nativeReport.values()) {
+      NSString *key = [NSString stringForStdString:
+          valuePair.second->display_name()];
+      NSString *value = [NSString stringForStdString:
+          valuePair.second->ToString()];
+
+      // Not expecting duplicate keys.
+      RTC_DCHECK(![values objectForKey:key]);
+      [values setObject:value forKey:key];
+    }
+    _values = values;
+  }
+  return self;
+}
+
+@end