Build dynamic iOS SDK.

- Places most ObjC code into webrtc/sdk/objc instead.
- New gyp targets to build, strip and export symbols for dylib.
- Removes old script used to generate dylib.

BUG=

Review URL: https://codereview.webrtc.org/1903663002

Cr-Commit-Position: refs/heads/master@{#12524}

webrtc/sdk/objc/Framework/Headers/WebRTC/RTCFileLogger.h

@@ -0,0 +1,77 @@
+/*
+ *  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 <Foundation/Foundation.h>
+
+#import <WebRTC/RTCMacros.h>
+
+typedef NS_ENUM(NSUInteger, RTCFileLoggerSeverity) {
+  RTCFileLoggerSeverityVerbose,
+  RTCFileLoggerSeverityInfo,
+  RTCFileLoggerSeverityWarning,
+  RTCFileLoggerSeverityError
+};
+
+typedef NS_ENUM(NSUInteger, RTCFileLoggerRotationType) {
+  RTCFileLoggerTypeCall,
+  RTCFileLoggerTypeApp,
+};
+
+NS_ASSUME_NONNULL_BEGIN
+
+// This class intercepts WebRTC logs and saves them to a file. The file size
+// will not exceed the given maximum bytesize. When the maximum bytesize is
+// reached, logs are rotated according to the rotationType specified.
+// For kRTCFileLoggerTypeCall, logs from the beginning and the end
+// are preserved while the middle section is overwritten instead.
+// For kRTCFileLoggerTypeApp, the oldest log is overwritten.
+// This class is not threadsafe.
+RTC_EXPORT
+@interface RTCFileLogger : NSObject
+
+// The severity level to capture. The default is kRTCFileLoggerSeverityInfo.
+@property(nonatomic, assign) RTCFileLoggerSeverity severity;
+
+// The rotation type for this file logger. The default is
+// kRTCFileLoggerTypeCall.
+@property(nonatomic, readonly) RTCFileLoggerRotationType rotationType;
+
+// Disables buffering disk writes. Should be set before |start|. Buffering
+// is enabled by default for performance.
+@property(nonatomic, assign) BOOL shouldDisableBuffering;
+
+// Default constructor provides default settings for dir path, file size and
+// rotation type.
+- (instancetype)init;
+
+// Create file logger with default rotation type.
+- (instancetype)initWithDirPath:(NSString *)dirPath
+                    maxFileSize:(NSUInteger)maxFileSize;
+
+- (instancetype)initWithDirPath:(NSString *)dirPath
+                    maxFileSize:(NSUInteger)maxFileSize
+                   rotationType:(RTCFileLoggerRotationType)rotationType
+    NS_DESIGNATED_INITIALIZER;
+
+// Starts writing WebRTC logs to disk if not already started. Overwrites any
+// existing file(s).
+- (void)start;
+
+// Stops writing WebRTC logs to disk. This method is also called on dealloc.
+- (void)stop;
+
+// Returns the current contents of the logs, or nil if start has been called
+// without a stop.
+- (NSData *)logData;
+
+@end
+
+NS_ASSUME_NONNULL_END
+