Use uniform spelling for "placeholder" in AHAT.

Test: mmma art/tools/ahat
Change-Id: Icedf149086fcccf53ba8e575bc17c4be749b05f0
diff --git a/tools/ahat/src/main/com/android/ahat/DocString.java b/tools/ahat/src/main/com/android/ahat/DocString.java
index 76e9e80..eda9b38 100644
--- a/tools/ahat/src/main/com/android/ahat/DocString.java
+++ b/tools/ahat/src/main/com/android/ahat/DocString.java
@@ -129,7 +129,7 @@
    *
    * Nothing is printed for a size of zero.
    * Set isPlaceHolder to true to indicate that the size field corresponds to
-   * for a place holder object that should be annotated specially.
+   * for a placeholder object that should be annotated specially.
    */
   public static DocString size(long size, boolean isPlaceHolder) {
     DocString string = new DocString();
diff --git a/tools/ahat/src/main/com/android/ahat/heapdump/AhatHeap.java b/tools/ahat/src/main/com/android/ahat/heapdump/AhatHeap.java
index 60c9a0d..a189945 100644
--- a/tools/ahat/src/main/com/android/ahat/heapdump/AhatHeap.java
+++ b/tools/ahat/src/main/com/android/ahat/heapdump/AhatHeap.java
@@ -37,7 +37,7 @@
   }
 
   /**
-   * Construct a place holder heap.
+   * Construct a placeholder heap.
    */
   private AhatHeap(String name, AhatHeap baseline) {
     mName = name;
@@ -48,7 +48,7 @@
   }
 
   /**
-   * Construct a new place holder heap that has the given baseline heap.
+   * Construct a new placeholder heap that has the given baseline heap.
    */
   static AhatHeap newPlaceHolderHeap(String name, AhatHeap baseline) {
     return new AhatHeap(name, baseline);
diff --git a/tools/ahat/src/main/com/android/ahat/heapdump/AhatInstance.java b/tools/ahat/src/main/com/android/ahat/heapdump/AhatInstance.java
index e62fb40..ebd96e9 100644
--- a/tools/ahat/src/main/com/android/ahat/heapdump/AhatInstance.java
+++ b/tools/ahat/src/main/com/android/ahat/heapdump/AhatInstance.java
@@ -686,7 +686,7 @@
   }
 
   /**
-   * Returns a new place holder instance corresponding to this instance.
+   * Returns a new placeholder instance corresponding to this instance.
    */
   AhatInstance newPlaceHolderInstance() {
     return new AhatPlaceHolderInstance(this);
diff --git a/tools/ahat/src/main/com/android/ahat/heapdump/AhatSnapshot.java b/tools/ahat/src/main/com/android/ahat/heapdump/AhatSnapshot.java
index 3634a1a..14dfe03 100644
--- a/tools/ahat/src/main/com/android/ahat/heapdump/AhatSnapshot.java
+++ b/tools/ahat/src/main/com/android/ahat/heapdump/AhatSnapshot.java
@@ -145,7 +145,7 @@
    * Returns a list of heaps in the snapshot in canonical order.
    * <p>
    * Note: modifications to the returned list are visible to this
-   * AhatSnapshot, which is used by diff to insert place holder heaps.
+   * AhatSnapshot, which is used by diff to insert placeholder heaps.
    *
    * @return list of heaps
    */
diff --git a/tools/ahat/src/main/com/android/ahat/heapdump/Diff.java b/tools/ahat/src/main/com/android/ahat/heapdump/Diff.java
index b35b424..ca00f17 100644
--- a/tools/ahat/src/main/com/android/ahat/heapdump/Diff.java
+++ b/tools/ahat/src/main/com/android/ahat/heapdump/Diff.java
@@ -154,9 +154,9 @@
   }
 
   /**
-   * Recursively create place holder instances for the given instance and
+   * Recursively create placeholder instances for the given instance and
    * every instance dominated by that instance.
-   * Returns the place holder instance created for the given instance.
+   * Returns the placeholder instance created for the given instance.
    * Adds all allocated placeholders to the given placeholders list.
    */
   private static AhatInstance createPlaceHolders(AhatInstance inst,
@@ -260,7 +260,7 @@
    *
    * This requires that instances have already been diffed. In particular, we
    * require all AhatClassObjs in one snapshot have corresponding (possibly
-   * place-holder) AhatClassObjs in the other snapshot.
+   * placeholder) AhatClassObjs in the other snapshot.
    */
   private static void sites(Site a, Site b) {
     // Set the sites as baselines of each other.
diff --git a/tools/ahat/src/main/com/android/ahat/heapdump/Diffable.java b/tools/ahat/src/main/com/android/ahat/heapdump/Diffable.java
index 18f63ce..90852e9 100644
--- a/tools/ahat/src/main/com/android/ahat/heapdump/Diffable.java
+++ b/tools/ahat/src/main/com/android/ahat/heapdump/Diffable.java
@@ -37,7 +37,7 @@
    * Returns true if this is a placeholder object.
    * A placeholder object is used to indicate there is some object in the
    * baseline heap dump that is not in this heap dump. In that case, we create
-   * a place holder object in this heap dump as an indicator of the
+   * a placeholder object in this heap dump as an indicator of the
    * object removed from the baseline heap dump.
    *
    * @return true if the object is a placeholder