Use 48dp bounding box for microphone on the NTP

BUG=594166

Change-Id: Ie5871930e089b8926f31a83854df6e8315d093a9
Reviewed-on: https://chromium-review.googlesource.com/c/1371820
Commit-Queue: Theresa <twellington@chromium.org>
Reviewed-by: Becky Zhou (OOO Dec 12 - Dec 31) <huayinz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615759}

chrome/android/java/res/layout/new_tab_page_layout.xml

@@ -39,8 +39,7 @@
         android:addStatesFromChildren="true"
         android:background="@drawable/ntp_search_box"
         android:orientation="horizontal"
-        android:paddingStart="@dimen/location_bar_lateral_padding"
-        android:paddingEnd="@dimen/location_bar_lateral_padding" >
+        android:paddingStart="@dimen/location_bar_lateral_padding" >
         <!-- TODO(crbug.com/900912): Fix and remove lint ignore -->
         <EditText
             tools:ignore="Autofill,LabelFor"
@@ -57,12 +56,20 @@
             android:gravity="center_vertical"
             android:inputType="text"
             android:singleLine="true" />
+        <!-- Padding start is applied so that microphone icon appears in the same location as it
+             does in the main url bar. The microphone button in the url bar is
+             location_bar_icon_width (28dp) wide with 4dp start padding. It is placed
+             location_bar_lateral_padding (10dp) from the edge of the omnibox background.
+             The 4dp start padding effectively leaves 44dp for a 24dp icon, so it will end up
+             10dp from the edge as well ((44 - 24) / 2). -->
         <org.chromium.ui.widget.ChromeImageView
             android:id="@+id/voice_search_button"
-            android:layout_width="wrap_content"
-            android:layout_height="wrap_content"
+            android:layout_width="48dp"
+            android:layout_height="match_parent"
+            android:paddingStart="4dp"
             android:contentDescription="@string/accessibility_toolbar_btn_mic"
             android:src="@drawable/btn_mic"
+            android:scaleType="centerInside"
             app:tint="@color/dark_mode_tint" />
     </view>
 

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

@@ -12,6 +12,7 @@ import android.graphics.drawable.Drawable;
 import android.graphics.drawable.RippleDrawable;
 import android.os.Build;
 import android.support.annotation.Nullable;
+import android.support.v4.view.ViewCompat;
 import android.text.Editable;
 import android.text.TextWatcher;
 import android.util.AttributeSet;
@@ -772,6 +773,12 @@ public class NewTabPageLayout extends LinearLayout implements TileGroup.Observer
      */
     void updateVoiceSearchButtonVisibility() {
         mVoiceSearchButton.setVisibility(mManager.isVoiceSearchEnabled() ? VISIBLE : GONE);
+        ViewCompat.setPaddingRelative(mSearchBoxView, ViewCompat.getPaddingStart(mSearchBoxView),
+                mSearchBoxView.getPaddingTop(),
+                mManager.isVoiceSearchEnabled() ? 0
+                                                : getResources().getDimensionPixelSize(
+                                                        R.dimen.location_bar_lateral_padding),
+                mSearchBoxView.getPaddingBottom());
     }
 
     @Override