Use the same shadow for the Android NTP fakebox than for the top omnibox.

chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java
index 95795e3e097f5abf02423dd8d52f99ee57c52f23..aba74e7ebd32a6d05444a3109494ef1267f60a93 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/NewTabPageLayout.java
@@ -6,11 +6,12 @@ package org.chromium.chrome.browser.ntp;
 
 import android.content.Context;
 import android.content.res.Resources;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
 import android.view.View;
 import android.widget.LinearLayout;
 
-import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.chrome.R;
 
 /**
@@ -36,6 +37,7 @@ public class NewTabPageLayout extends LinearLayout {
     private final int mTabStripHeight;
 
     private int mParentViewportHeight;
+    private int mSearchboxViewShadowWidth;
 
     private boolean mCardsUiEnabled;
     private View mTopSpacer;  // Spacer above search logo.
@@ -49,7 +51,6 @@ public class NewTabPageLayout extends LinearLayout {
     private LogoView mSearchProviderLogoView;
     private View mSearchBoxView;
     private MostVisitedLayout mMostVisitedLayout;
-

[Theresa, 2016/05/26 21:54:41]

nit: please add this line back.

     /**
      * Constructor for inflating from XML.
      */
@@ -142,7 +143,8 @@ public class NewTabPageLayout extends LinearLayout {
         // Make the search box and logo as wide as the most visited items.
         if (mMostVisitedLayout.getVisibility() != GONE) {
             final int width = mMostVisitedLayout.getMeasuredWidth() - mMostVisitedLayoutBleed;
-            setMeasure(mSearchBoxView, width, mSearchBoxView.getMeasuredHeight());
+            setMeasure(mSearchBoxView, width + mSearchboxViewShadowWidth,
+                    mSearchBoxView.getMeasuredHeight());
             setMeasure(mSearchProviderLogoView, width, mSearchProviderLogoView.getMeasuredHeight());
         }
     }
@@ -168,16 +170,37 @@ public class NewTabPageLayout extends LinearLayout {
     }
 
     /**
-     * Set the search box style. Modify the search box to enable material when snippets or
-     * material design is enabled.
+     * Set the search box style, adding a shadow if required.
      */
     private void setSearchBoxStyle() {
-        if (NtpColorUtils.shouldUseMaterialColors()
-                && ApiCompatibilityUtils.setElevation(mSearchBoxView,
-                           getResources().getDimensionPixelSize(R.dimen.toolbar_elevation))) {
-            // Replace drawable with one that does not contain a border.
-            mSearchBoxView.setBackgroundResource(R.drawable.bg_ntp_search_box_material);
-        }
+        if (!NtpColorUtils.shouldUseMaterialColors()) return;
+
+        Drawable background = mSearchBoxView.getBackground();

[Theresa, 2016/05/26 17:47:26]

Can the padding be added via xml? I'm hoping we can avoid all of this manual
calculation.

Since the current background (R.drawable.bg_ntp_search_box) is just being
replaced with R.drawable.textbox, can we change new_tab_page_layout.xml to use
R.drawable.textbox as the search_box background instead?

Just to double check, the screenshots in the email thread were using
R.drawable.textbox as the background?

[Bernhard Bauer, 2016/05/26 19:43:57]

The reason I'm doing this in code is that we still have a flag to turn this off
(the shadow goes with the more-material NTP background). Once that flag is
removed, I can switch over to doing everything in XML.
That's correct.

[Theresa, 2016/05/26 21:54:41]

Can you use defined dimens that represent the correct new layout params/padding
instead of calculating it?

[Bernhard Bauer, 2016/05/27 12:16:41]

Done. Note however that keeping the exactly same positioning of e.g. the search
box contents isn't possible without calculations, because the padding for the
default background is specified in pixels, whereas the padding for the
nine-patch is in dp. I've adjusted the values so that it looks as closely to the
original on an XXHDPI device as possible without having to go into fractional
dp's.

+        Rect padding = new Rect();
+        background.getPadding(padding);
+
+        Resources resources = getContext().getResources();
+        Drawable shadow = resources.getDrawable(R.drawable.textbox);

[Theresa, 2016/05/26 21:54:41]

Resources.getDrawable() is deprecated. Use ApiCompatibilityUtils#getDrawable().

[Bernhard Bauer, 2016/05/27 12:16:41]

Thanks! That code is gone now though.

+        Rect shadowPadding = new Rect();
+        shadow.getPadding(shadowPadding);
+
+        // Adjust the margins to remove the padding.

[Theresa, 2016/05/26 21:54:41]

Why does the padding need to be removed just to be added back?

[Bernhard Bauer, 2016/05/27 12:16:41]

Sorry, that comment should have been a bit more detailed. The |textbox| drawable
extends further than the default one does, because it includes the shadow. So,
in order to keep the apparent border and the contents in the same position, I
have to subtract the extrusion value (which is the |textbox| drawable's padding)
from the margins but add them to the existing padding for the default
background. Anyway, that code is gone now.

+        MarginLayoutParams layoutParams = (MarginLayoutParams) mSearchBoxView.getLayoutParams();
+        layoutParams.topMargin -= shadowPadding.top;
+        layoutParams.bottomMargin -= shadowPadding.bottom;
+        layoutParams.leftMargin -= shadowPadding.left;
+        layoutParams.rightMargin -= shadowPadding.right;
+        layoutParams.height += shadowPadding.bottom + shadowPadding.top;
+        // Width will be adjusted in onMeasure();
+        mSearchboxViewShadowWidth = shadowPadding.left + shadowPadding.right;
+
+        // Add the extra padding back.
+        mSearchBoxView.setBackground(shadow);
+        mSearchBoxView.setPadding(
+                padding.left + shadowPadding.left,
+                padding.top + shadowPadding.top,
+                padding.right + shadowPadding.right,
+                padding.bottom + shadowPadding.bottom);
     }
 
     /**