Remove some global defines and build flags.

build/config/features.gni

Index: build/config/features.gni
diff --git a/build/config/features.gni b/build/config/features.gni
index 738a1b9077ec16c4a86b9d0917a5e7ffafa2229d..6b144415e4a65d3c159a594cc5d3134bb0fb86b9 100644
--- a/build/config/features.gni
+++ b/build/config/features.gni
@@ -97,9 +97,6 @@ enable_spellcheck = !is_ios
 # Use the operating system's spellchecker rather than hunspell.
 use_browser_spellchecker = is_android || is_mac
 
-# Use Minikin hyphenation engine.
-use_minikin_hyphenation = is_android
-
 # The seccomp-bpf sandbox is only supported on five architectures
 # currently.
 # Do not disable seccomp_bpf anywhere without talking to
@@ -123,9 +120,6 @@ enable_themes = !is_android && !is_ios
 enable_rlz_support = is_win || is_mac || is_ios || is_chromeos
 enable_rlz = is_chrome_branded && enable_rlz_support
 
-# Image loader extension is enabled on ChromeOS only.
-enable_image_loader_extension = is_chromeos
-
 # Chrome OS: whether to also build the upcoming version of
 # ChromeVox, which can then be enabled via a command-line switch.
 enable_chromevox_next = false