Add support for optional titles in action modes

Optional titles will only be displayed in the CAB if they entirely fit
instead of ellipsizing.

Fixes bug 5821883

Change-Id: I0cfd6d4fd34a4fa9f520499d577706da30606811
diff --git a/api/current.txt b/api/current.txt
index e0dad49..c43c45f 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -21935,12 +21935,14 @@
     method public java.lang.Object getTag();
     method public abstract java.lang.CharSequence getTitle();
     method public abstract void invalidate();
+    method public boolean isTitleOptional();
     method public abstract void setCustomView(android.view.View);
     method public abstract void setSubtitle(java.lang.CharSequence);
     method public abstract void setSubtitle(int);
     method public void setTag(java.lang.Object);
     method public abstract void setTitle(java.lang.CharSequence);
     method public abstract void setTitle(int);
+    method public void setTitleOptionalHint(boolean);
   }
 
   public static abstract interface ActionMode.Callback {
diff --git a/core/java/android/inputmethodservice/ExtractEditLayout.java b/core/java/android/inputmethodservice/ExtractEditLayout.java
index 220214b..5696839 100644
--- a/core/java/android/inputmethodservice/ExtractEditLayout.java
+++ b/core/java/android/inputmethodservice/ExtractEditLayout.java
@@ -124,6 +124,12 @@
         }
 
         @Override
+        public boolean isTitleOptional() {
+            // Not only is it optional, it will *never* be shown.
+            return true;
+        }
+
+        @Override
         public void setCustomView(View view) {
             // Custom view is not supported here.
         }
diff --git a/core/java/android/view/ActionMode.java b/core/java/android/view/ActionMode.java
index c1c7fe2..0ba5fdb 100644
--- a/core/java/android/view/ActionMode.java
+++ b/core/java/android/view/ActionMode.java
@@ -104,6 +104,32 @@
     public abstract void setSubtitle(int resId);
 
     /**
+     * Set whether or not the title/subtitle display for this action mode
+     * is optional.
+     *
+     * <p>In many cases the supplied title for an action mode is merely
+     * meant to add context and is not strictly required for the action
+     * mode to be useful. If the title is optional, the system may choose
+     * to hide the title entirely rather than truncate it due to a lack
+     * of available space.</p>
+     *
+     * <p>Note that this is merely a hint; the underlying implementation
+     * may choose to ignore this setting under some circumstances.</p>
+     *
+     * @param titleOptional true if the title only presents optional information.
+     */
+    public void setTitleOptionalHint(boolean titleOptional) {
+    }
+
+    /**
+     * @return true if this action mode considers the title and subtitle fields
+     *         as optional. Optional titles may not be displayed to the user.
+     */
+    public boolean isTitleOptional() {
+        return false;
+    }
+
+    /**
      * Set a custom view for this action mode. The custom view will take the place of
      * the title and subtitle. Useful for things like search boxes.
      *
diff --git a/core/java/android/webkit/SelectActionModeCallback.java b/core/java/android/webkit/SelectActionModeCallback.java
index cdf20f6..2a770f5 100644
--- a/core/java/android/webkit/SelectActionModeCallback.java
+++ b/core/java/android/webkit/SelectActionModeCallback.java
@@ -53,10 +53,8 @@
         mode.getMenuInflater().inflate(com.android.internal.R.menu.webview_copy, menu);
 
         final Context context = mWebView.getContext();
-        boolean allowText = context.getResources().getBoolean(
-                com.android.internal.R.bool.config_allowActionMenuItemTextWithIcon);
-        mode.setTitle(allowText ?
-                context.getString(com.android.internal.R.string.textSelectionCABTitle) : null);
+        mode.setTitle(context.getString(com.android.internal.R.string.textSelectionCABTitle));
+        mode.setTitleOptionalHint(true);
 
         // If the action mode UI we're running in isn't capable of taking window focus
         // the user won't be able to type into the find on page UI. Disable this functionality.
diff --git a/core/java/android/widget/TextView.java b/core/java/android/widget/TextView.java
index a4087d5..1620929 100644
--- a/core/java/android/widget/TextView.java
+++ b/core/java/android/widget/TextView.java
@@ -10363,9 +10363,9 @@
             boolean allowText = getContext().getResources().getBoolean(
                     com.android.internal.R.bool.config_allowActionMenuItemTextWithIcon);
 
-            mode.setTitle(allowText ?
-                    mContext.getString(com.android.internal.R.string.textSelectionCABTitle) : null);
+            mode.setTitle(mContext.getString(com.android.internal.R.string.textSelectionCABTitle));
             mode.setSubtitle(null);
+            mode.setTitleOptionalHint(true);
 
             int selectAllIconId = 0; // No icon by default
             if (!allowText) {
diff --git a/core/java/com/android/internal/app/ActionBarImpl.java b/core/java/com/android/internal/app/ActionBarImpl.java
index afb5bf1..f3486bd 100644
--- a/core/java/com/android/internal/app/ActionBarImpl.java
+++ b/core/java/com/android/internal/app/ActionBarImpl.java
@@ -748,6 +748,16 @@
         }
         
         @Override
+        public void setTitleOptionalHint(boolean titleOptional) {
+            mContextView.setTitleOptional(titleOptional);
+        }
+
+        @Override
+        public boolean isTitleOptional() {
+            return mContextView.isTitleOptional();
+        }
+
+        @Override
         public View getCustomView() {
             return mCustomView != null ? mCustomView.get() : null;
         }
diff --git a/core/java/com/android/internal/view/StandaloneActionMode.java b/core/java/com/android/internal/view/StandaloneActionMode.java
index edf4443..4b681ec 100644
--- a/core/java/com/android/internal/view/StandaloneActionMode.java
+++ b/core/java/com/android/internal/view/StandaloneActionMode.java
@@ -72,6 +72,16 @@
     }
 
     @Override
+    public void setTitleOptionalHint(boolean titleOptional) {
+        mContextView.setTitleOptional(titleOptional);
+    }
+
+    @Override
+    public boolean isTitleOptional() {
+        return mContextView.isTitleOptional();
+    }
+
+    @Override
     public void setCustomView(View view) {
         mContextView.setCustomView(view);
         mCustomView = view != null ? new WeakReference<View>(view) : null;
diff --git a/core/java/com/android/internal/widget/ActionBarContextView.java b/core/java/com/android/internal/widget/ActionBarContextView.java
index fa16527..16f08f5 100644
--- a/core/java/com/android/internal/widget/ActionBarContextView.java
+++ b/core/java/com/android/internal/widget/ActionBarContextView.java
@@ -56,6 +56,7 @@
     private int mTitleStyleRes;
     private int mSubtitleStyleRes;
     private Drawable mSplitBackground;
+    private boolean mTitleOptional;
 
     private Animator mCurrentAnimation;
     private boolean mAnimateInOnLayout;
@@ -354,7 +355,18 @@
         }
 
         if (mTitleLayout != null && mCustomView == null) {
-            availableWidth = measureChildView(mTitleLayout, availableWidth, childSpecHeight, 0);
+            if (mTitleOptional) {
+                final int titleWidthSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
+                mTitleLayout.measure(titleWidthSpec, childSpecHeight);
+                final int titleWidth = mTitleLayout.getMeasuredWidth();
+                final boolean titleFits = titleWidth <= availableWidth;
+                if (titleFits) {
+                    availableWidth -= titleWidth;
+                }
+                mTitleLayout.setVisibility(titleFits ? VISIBLE : GONE);
+            } else {
+                availableWidth = measureChildView(mTitleLayout, availableWidth, childSpecHeight, 0);
+            }
         }
 
         if (mCustomView != null) {
@@ -460,7 +472,7 @@
             }
         }
 
-        if (mTitleLayout != null && mCustomView == null) {
+        if (mTitleLayout != null && mCustomView == null && mTitleLayout.getVisibility() != GONE) {
             x += positionChild(mTitleLayout, x, y, contentHeight);
         }
         
@@ -512,4 +524,15 @@
             super.onInitializeAccessibilityEvent(event);
         }
     }
+
+    public void setTitleOptional(boolean titleOptional) {
+        if (titleOptional != mTitleOptional) {
+            requestLayout();
+        }
+        mTitleOptional = titleOptional;
+    }
+
+    public boolean isTitleOptional() {
+        return mTitleOptional;
+    }
 }