Add cld2_table_size variable to GN build.

This variable has been in common.gypi for some time, but was missing from GN.

BUG=528257

Review URL: https://codereview.chromium.org/1306053014

Cr-Original-Commit-Position: refs/heads/master@{#347576}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: b32a1daf9763b66e7f12a3e88e4b526589dd8479

common.gypi

@@ -564,8 +564,8 @@
       # For CLD2, the size of the tables that should be included in the build
       # Only evaluated if cld_version == 2.
       # See third_party/cld_2/cld_2.gyp for more information.
-      #   0: Small tables, lower accuracy
+      #   0: Small tables, high accuracy
-      #   2: Large tables, high accuracy
+      #   2: Large tables, higher accuracy
       'cld2_table_size%': 2,
 
       # Enable spell checker.

config/features.gni

@@ -129,6 +129,12 @@ declare_args() {
 #   2: Use only CLD2.
 cld_version = 2
 
+if (is_android || is_ios) {
+  cld2_table_size = 0  # Small, accurate tables
+} else {
+  cld2_table_size = 2  # Larger, more accurate tables
+}
+
 # libudev usage. This currently only affects the content layer.
 use_udev = is_linux