[cronet] Expose API to set experimental options

components/cronet/ios/Cronet.mm

Index: components/cronet/ios/Cronet.mm
diff --git a/components/cronet/ios/Cronet.mm b/components/cronet/ios/Cronet.mm
index b883049b52d3fefab00ba5ac7b4ec128cc676e90..3adc49185c673fdef413d8f2095b183c75982316 100644
--- a/components/cronet/ios/Cronet.mm
+++ b/components/cronet/ios/Cronet.mm
@@ -37,6 +37,7 @@ BOOL gQuicEnabled = NO;
 cronet::URLRequestContextConfig::HttpCacheType gHttpCache =
     cronet::URLRequestContextConfig::HttpCacheType::DISK;
 ScopedVector<cronet::URLRequestContextConfig::QuicHint> gQuicHints;
+NSString* gExperimentalOptions = @"{}";
 NSString* gUserAgent = nil;
 BOOL gUserAgentPartial = NO;
 NSString* gSslKeyLogFileName = nil;
@@ -168,6 +169,11 @@ class CronetHttpProtocolHandlerDelegate
       base::SysNSStringToUTF8(host), port, altPort));
 }
 
++ (void)setExperimentalOptions:(NSString*)experimentalOptions {
+  [self checkNotStarted];
+  gExperimentalOptions = experimentalOptions;
+}
+
 + (void)setUserAgent:(NSString*)userAgent partial:(BOOL)partial {
   [self checkNotStarted];
   gUserAgent = userAgent;
@@ -176,7 +182,7 @@ class CronetHttpProtocolHandlerDelegate
 
 + (void)setSslKeyLogFileName:(NSString*)sslKeyLogFileName {
   [self checkNotStarted];
-  gSslKeyLogFileName = sslKeyLogFileName;
+  gSslKeyLogFileName = [self getNetLogPathForFile:sslKeyLogFileName];
 }
 
 + (void)setHttpCacheType:(CRNHttpCacheType)httpCacheType {
@@ -213,6 +219,8 @@ class CronetHttpProtocolHandlerDelegate
 
   gChromeNet.Get()->set_http2_enabled(gHttp2Enabled);
   gChromeNet.Get()->set_quic_enabled(gQuicEnabled);
+  gChromeNet.Get()->set_experimental_options(
+      base::SysNSStringToUTF8(gExperimentalOptions));
   gChromeNet.Get()->set_http_cache(gHttpCache);
   gChromeNet.Get()->set_ssl_key_log_file_name(
       base::SysNSStringToUTF8(gSslKeyLogFileName));