Resize only the virtual viewport when the OSK triggers a resize.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index b8b4d86643b5fd10c96e8521a3ba4b401924c389..5008141f6352c67a8e6e38572c07a2fa2402d655 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -620,6 +620,11 @@ const FeatureEntry kFeatureEntries[] = {
      IDS_FLAGS_WEBAUDIO_DESCRIPTION,
      kOsAndroid,
      SINGLE_DISABLE_VALUE_TYPE(switches::kDisableWebAudio)},
+    {"enable-osk-overscroll",
+     IDS_FLAGS_ENABLE_OSK_OVERSCROLL_NAME,
+     IDS_FLAGS_ENABLE_OSK_OVERSCROLL_DESCRIPTION,
+     kOsAndroid,
+     SINGLE_VALUE_TYPE(switches::kEnableOSKOverscroll)},
 #endif
   // Native client is compiled out when DISABLE_NACL is defined.
 #if !defined(DISABLE_NACL)