Make sure progress bar is attached before init

This change makes sure that the progress bar has been attached to the
hierarchy before trying to initialize it. Many of the null checks have
also been removed since the progress bar is now created in the
constructor.

BUG=716382

Review-Url: https://codereview.chromium.org/2853943002
Cr-Commit-Position: refs/heads/master@{#468532}

chrome/android/java/src/org/chromium/chrome/browser/toolbar/ToolbarLayout.java

@@ -101,8 +101,9 @@ public abstract class ToolbarLayout extends FrameLayout implements Toolbar {
             @Override
             public void onLayoutChange(View view, int left, int top, int right, int bottom,
                     int oldLeft, int oldTop, int oldRight, int oldBottom) {
-                if (isNativeLibraryReady()) mProgressBar.initializeAnimation();
-                addProgressBarToHierarchy();
+                if (isNativeLibraryReady() && mProgressBar.getParent() != null) {
+                    mProgressBar.initializeAnimation();
+                }
                 mProgressBar.setTopMargin(getProgressBarTopMargin());
 
                 // Since this only needs to happen once, remove this listener from the view.
@@ -217,7 +218,13 @@ public abstract class ToolbarLayout extends FrameLayout implements Toolbar {
      */
     public void onNativeLibraryReady() {
         mNativeLibraryReady = true;
-        if (mProgressBar != null) mProgressBar.initializeAnimation();
+        if (mProgressBar.getParent() != null) mProgressBar.initializeAnimation();
+    }
+
+    @Override
+    protected void onAttachedToWindow() {
+        super.onAttachedToWindow();
+        addProgressBarToHierarchy();
     }
 
     /**
@@ -264,8 +271,6 @@ public abstract class ToolbarLayout extends FrameLayout implements Toolbar {
      * Add the toolbar's progress bar to the view hierarchy.
      */
     protected void addProgressBarToHierarchy() {
-        if (mProgressBar == null) return;
-
         ViewGroup controlContainer =
                 (ViewGroup) getRootView().findViewById(R.id.control_container);
         int progressBarPosition = UiUtils.insertAfter(
@@ -596,9 +601,7 @@ public abstract class ToolbarLayout extends FrameLayout implements Toolbar {
      * Starts load progress.
      */
     protected void startLoadProgress() {
-        if (mProgressBar != null) {
-            mProgressBar.start();
-        }
+        mProgressBar.start();
     }
 
     /**
@@ -606,9 +609,7 @@ public abstract class ToolbarLayout extends FrameLayout implements Toolbar {
      * @param progress The load progress between 0 and 1.
      */
     protected void setLoadProgress(float progress) {
-        if (mProgressBar != null) {
-            mProgressBar.setProgress(progress);
-        }
+        mProgressBar.setProgress(progress);
     }
 
     /**
@@ -617,16 +618,14 @@ public abstract class ToolbarLayout extends FrameLayout implements Toolbar {
      *                        recognize the last state.
      */
     protected void finishLoadProgress(boolean delayed) {
-        if (mProgressBar != null) {
-            mProgressBar.finish(delayed);
-        }
+        mProgressBar.finish(delayed);
     }
 
     /**
      * @return True if the progress bar is started.
      */
     protected boolean isProgressStarted() {
-        return mProgressBar != null ? mProgressBar.isStarted() : false;
+        return mProgressBar.isStarted();
     }
 
     /**