Cache CCT dynamic module until onTrimMemory.

This functionality is guarded by the CCTModuleCache feature, which is
disabled by default.

Bug: 853793
Change-Id: I4ec6de1c43c47bf2481b1cb8fcbe171016f395ce
Reviewed-on: https://chromium-review.googlesource.com/c/1268340
Reviewed-by: Ted Choc <[email protected]>
Commit-Queue: Michael van Ouwerkerk <[email protected]>
Cr-Commit-Position: refs/heads/master@{#597854}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 9b9d96b..7cc0e3e 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -2221,6 +2221,11 @@
 const char kCCTModuleDescription[] =
     "Enables a dynamically loaded module in Chrome Custom Tabs, on Android.";
 
+const char kCCTModuleCacheName[] = "Chrome Custom Tabs Module Cache";
+const char kCCTModuleCacheDescription[] =
+    "Enables a cache for dynamically loaded modules in Chrome Custom Tabs, "
+    "on Android.";
+
 const char kChromeDuetName[] = "Chrome Duet";
 const char kChromeDuetDescription[] =
     "Enables Chrome Duet, split toolbar Chrome Home, on Android.";