[ios] Fix minimum required version of Xcode

Bug: none
Change-Id: I425a7e8b1bc46bb7d650ebb2fc873ca5f0f115d1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2299342
Commit-Queue: Sylvain Defresne <[email protected]>
Reviewed-by: Robbie Gibson <[email protected]>
Cr-Commit-Position: refs/heads/master@{#788593}
diff --git a/docs/ios/build_instructions.md b/docs/ios/build_instructions.md
index dd3f606..188fd0bd 100644
--- a/docs/ios/build_instructions.md
+++ b/docs/ios/build_instructions.md
@@ -13,7 +13,7 @@
 ## System requirements
 
 * A 64-bit Mac running 10.12.6 or later.
-* [Xcode](https://developer.apple.com/xcode) 10.0+.
+* [Xcode](https://developer.apple.com/xcode) 11.4+.
 * The current version of the JDK (required for the Closure compiler).
 
 ## Install `depot_tools`