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

chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java b/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
index 22b29fe59eb486db769473727de4b2bda4e29b2e..69e0dbcfd7828d6d4ce555408791adaf39d256c8 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ChromeActivity.java
@@ -204,6 +204,7 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
     private ActivityWindowAndroid mWindowAndroid;
     private ChromeFullscreenManager mFullscreenManager;
     private CompositorViewHolder mCompositorViewHolder;
+    private InsetConsumerView mInsetConsumerView;
     private ContextualSearchManager mContextualSearchManager;
     private ReaderModeManager mReaderModeManager;
     private SnackbarManager mSnackbarManager;
@@ -347,6 +348,23 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
 
         mCompositorViewHolder = (CompositorViewHolder) findViewById(R.id.compositor_view_holder);
         mCompositorViewHolder.setRootView(getWindow().getDecorView().getRootView());
+
+        // Setting fitsSystemWindows to false ensures that the parent views in
+        // the View hierarchy don't consume the insets. ContentViewCore needs
+        // the insets to determine the portion of the screen obscured by
+        // non-content displaying things such as the OSK.
+        View parent = mCompositorViewHolder;
+        while (parent.getParent() != null && parent.getParent() instanceof View) {
+            parent = (View) parent.getParent();
+            parent.setFitsSystemWindows(false);
+        }
+        // InsetConsumerView consumes the insets instead, so that the actual
+        // value of the insets can be stored.
+        mInsetConsumerView = (InsetConsumerView) findViewById(R.id.inset_consumer_view);
+        if (mInsetConsumerView != null) {
+            mInsetConsumerView.setFitsSystemWindows(true);
+            mInsetConsumerView.setTabModelSelector(getTabModelSelector());
+        }
     }
 
     /**
@@ -526,6 +544,10 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
         if (mAssistStatusHandler != null) {
             mAssistStatusHandler.setTabModelSelector(tabModelSelector);
         }
+
+        if (mInsetConsumerView != null) {
+            mInsetConsumerView.setTabModelSelector(tabModelSelector);
+        }
     }
 
     @Override