iOS: Cleanup buildbot JSON files + bump iOS version to 10.0

webrtc/build/ios/client.webrtc/iOS64_Debug_(GYP).json

Index: webrtc/build/ios/client.webrtc/iOS64_Debug_(GYP).json
diff --git a/webrtc/build/ios/client.webrtc/iOS64_Debug_(GYP).json b/webrtc/build/ios/client.webrtc/iOS64_Debug_(GYP).json
deleted file mode 100644
index 9ad4a55c3b405fe8fe305ca94eba903e90ca749e..0000000000000000000000000000000000000000
--- a/webrtc/build/ios/client.webrtc/iOS64_Debug_(GYP).json
+++ /dev/null
@@ -1,55 +0,0 @@
-{
-  "owners": [
-    "kjellander"
-  ],
-  "comments": [
-    "Builder for 64-bit devices.",
-    "GYP_DEFINES and gn_args in this file are only used during runhooks; ",
-    "webrtc/build/mb_config.pyl decides the generated projects that are compiled."
-  ],
-  "xcode version": "8.0",
-  "GYP_DEFINES": [
-    "use_goma=1",
-    "gomadir=$(goma_dir)",
-    "chromium_ios_signing=0",
-    "component=static_library",
-    "target_arch=arm64",
-    "include_examples=0",
-    "include_tests=0",
-    "include_ilbc=0",
-    "build_expat=0",
-    "build_json=0",
-    "build_libevent=0",
-    "build_libjpeg=0",
-    "build_libsrtp=0",
-    "build_libvpx=0",
-    "build_libyuv=0",
-    "build_openmax_dl=0",
-    "build_opus=0",
-    "build_protobuf=0",
-    "build_ssl=0",
-    "build_usrsctp=0",
-    "enable_video=0",
-    "linux_use_bundled_binutils=0",
-    "rtc_use_openmax_dl=1",
-    "use_openssl=1",
-    "use_x11=0",
-    "use_gtk=0"
-  ],
-  "gn_args": [
-    "is_debug=true",
-    "target_os=\"ios\"",
-    "ios_enable_code_signing=false",
-    "is_component_build=false",
-    "use_goma=true",
-    "goma_dir=\"$(goma_dir)\"",
-    "target_cpu=\"arm64\""
-  ],
-  "mb_type": "gyp",
-  "compiler": "ninja",
-  "additional_compile_targets": [ "all" ],
-  "configuration": "Debug",
-  "sdk": "iphoneos9.0",
-  "tests": [
-  ]
-}