Upgrade folly to v2018.10.22.00 for iOS (#21976)

Summary:
Fixes #20302 (For iOS)

Note:
------

1. Checked the changes did not break CocoaPods integration.
2. The change for glog copying header into exported/ is to prevent build break for folly.
    `folly/detail/Demangle.h` will try to use libstdc++'s demangle.h. Unfortunately, glog also has a demangle.h in source code. So I copy exported headers and only search headers in exported/ folder during build.
Pull Request resolved: facebook/react-native#21976

Reviewed By: hramos

Differential Revision: D12818131

Pulled By: fkgozali

fbshipit-source-id: b3c637d09d1b3adde0ea15c82eb56e28f846885b

Podfile.lock

@@ -1,7 +1,7 @@
 PODS:
  - boost-for-react-native (1.63.0)
  - DoubleConversion (1.1.6)
- - Folly (2016.10.31.00):
+ - Folly (2018.10.22.00):
  - boost-for-react-native
  - DoubleConversion
  - glog
@@ -11,22 +11,22 @@ PODS:
  - React/Core (1000.0.0):
  - yoga (= 1000.0.0.React)
  - React/CxxBridge (1000.0.0):
- - Folly (= 2016.10.31.00)
+ - Folly (= 2018.10.22.00)
  - React/Core
  - React/cxxreact
  - React/jsiexecutor
  - React/cxxreact (1000.0.0):
  - boost-for-react-native (= 1.63.0)
- - Folly (= 2016.10.31.00)
+ - Folly (= 2018.10.22.00)
  - React/jsinspector
  - React/DevSupport (1000.0.0):
  - React/Core
  - React/RCTWebSocket
  - React/fishhook (1000.0.0)
  - React/jsi (1000.0.0):
- - Folly (= 2016.10.31.00)
+ - Folly (= 2018.10.22.00)
  - React/jsiexecutor (1000.0.0):
- - Folly (= 2016.10.31.00)
+ - Folly (= 2018.10.22.00)
  - React/cxxreact
  - React/jsi
  - React/jsinspector (1000.0.0)
@@ -104,9 +104,9 @@ EXTERNAL SOURCES:
 SPEC CHECKSUMS:
  boost-for-react-native: 39c7adb57c4e60d6c5479dd8623128eb5b3f0f2c
  DoubleConversion: bb338842f62ab1d708ceb63ec3d999f0f3d98ecd
- Folly: c89ac2d5c6ab169cd7397ef27485c44f35f742c7
- glog: 848747cb7af3aac910395f03626d7f63636e8ce6
- React: 8cb457c5485e7640094a7df86fcdb6d1e56e182c
+ Folly: cd7933b82a5f7673ed71bafe631f44a575ae77ab
+ glog: aefd1eb5dda2ab95ba0938556f34b98e2da3a60d
+ React: 9b873b38b92ed8012d7cdf3b965477095ed364c4
  yoga: b1ce48b6cf950b98deae82838f5173ea7cf89e85
 
 PODFILE CHECKSUM: 7af77fbc34af9646e8c6389e7e2c0b4663bb16d9