Bug 1308317 - Part 2: Remove nsSupportsArray::MoveElement. r=froydnj

|MoveElement| is not scriptable and unused in our codebase.

MozReview-Commit-ID: CBe8WZHG1JG

xpcom/ds/nsISupportsArray.idl

@@ -63,9 +63,6 @@ interface nsISupportsArray : nsICollection {
 
   nsISupportsArray clone();
 
-  [notxpcom] boolean MoveElement(in long aFrom,
-                                 in long aTo);
-
   [notxpcom] boolean RemoveElementsAt(in unsigned long aIndex,
                                       in unsigned long aCount);
 

xpcom/ds/nsSupportsArray.cpp

@@ -360,36 +360,6 @@ nsSupportsArray::RemoveLastElement(const nsISupports* aElement)
   return false;
 }
 
-NS_IMETHODIMP_(bool)
-nsSupportsArray::MoveElement(int32_t aFrom, int32_t aTo)
-{
-  nsISupports* tempElement;
-
-  if (aTo == aFrom) {
-    return true;
-  }
-
-  if (aTo < 0 || aFrom < 0 ||
-      (uint32_t)aTo >= mCount || (uint32_t)aFrom >= mCount) {
-    // can't extend the array when moving an element.  Also catches mImpl = null
-    return false;
-  }
-  tempElement = mArray[aFrom];
-
-  if (aTo < aFrom) {
-    // Moving one element closer to the head; the elements inbetween move down
-    ::memmove(mArray + aTo + 1, mArray + aTo,
-              (aFrom - aTo) * sizeof(mArray[0]));
-    mArray[aTo] = tempElement;
-  } else { // already handled aFrom == aTo
-    // Moving one element closer to the tail; the elements inbetween move up
-    ::memmove(mArray + aFrom, mArray + aFrom + 1,
-              (aTo - aFrom) * sizeof(mArray[0]));
-    mArray[aTo] = tempElement;
-  }
-
-  return true;
-}
 
 NS_IMETHODIMP
 nsSupportsArray::Clear(void)

xpcom/ds/nsSupportsArray.h

@@ -56,7 +56,6 @@ public:
   }
   // XXX this is badly named - should be RemoveFirstElement
   MOZ_MUST_USE NS_IMETHOD RemoveElement(nsISupports* aElement) override;
-  MOZ_MUST_USE NS_IMETHOD_(bool) MoveElement(int32_t aFrom, int32_t aTo) override;
   NS_IMETHOD Enumerate(nsIEnumerator** aResult) override;
   NS_IMETHOD Clear(void) override;