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 0c1a139b05fcdf274a7524a697a33455fca543c7..0b10ff920482988acba87ef5e9d1c722b93ebc54 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;
@@ -343,6 +344,23 @@ 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) {

[aelias_OOO_until_Jul13, 2016/01/28 05:04:55]

This can be simplified to:

for (View parent = mCompositorViewHolder; parent instanceof View; parent =
parent.getParent()) {
  parent.setFitsSystemWindows(false);
}

[ymalik, 2016/02/11 01:06:22]

We don't check here if the actual parent of the view is an instance of View.
Instead, we check if the View is an instance of View which is always true.

[aelias_OOO_until_Jul13, 2016/02/24 02:43:58]

OK, I stand corrected.  Anyway, at least please delete "parent.getParent() !=
null" check because that's already considered by instanceof.

[ymalik, 2016/03/03 02:10:17]

Done.

+            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);

[aelias_OOO_until_Jul13, 2016/01/28 05:04:55]

The Android docs on this method says "Note that if you are providing your own
implementation of fitSystemWindows(Rect), then there is no need to set this flag
to true -- your implementation will be overriding the default implementation
that checks this flag."

[bokan, 2016/01/28 15:53:41]

I think you need to set it since the override of fitSystemWindows calls the
super method.

[aelias_OOO_until_Jul13, 2016/02/24 02:43:58]

How about simply not calling super.fitSystemWindows in our override then, like
the Android docs suggest?

[ymalik, 2016/03/03 02:10:17]

super.fitSystemWindows is what actually applies the insets. The override in
InsetConsumerView just stores it, so we need to call it.

+            mInsetConsumerView.setTabModelSelector(getTabModelSelector());
+        }
     }
 
     /**
@@ -522,6 +540,10 @@ public abstract class ChromeActivity extends AsyncInitializationActivity
         if (mAssistStatusHandler != null) {
             mAssistStatusHandler.setTabModelSelector(tabModelSelector);
         }
+
+        if (mInsetConsumerView != null) {
+            mInsetConsumerView.setTabModelSelector(tabModelSelector);
+        }
     }
 
     @Override