AArch64: Make AssetAtlasService 64-bit compatible

Changes in this patch include

[x] Long(64-bit) is used to store native pointers in
    AssetAtlasService and related classes as they can be 64-bit.

[x] Some minor changes have been done to conform with
    standard JNI practice (e.g. use of jint instead of int
    in JNI function prototypes)

Signed-off-by: Ashok Bhat <ashok.bhat@arm.com>

(cherry-picked from 4de3f481bc59ab4b766dc027e41aff7cda9d62f7)

Change-Id: If22daf40eef46f8df9f94d65ddcc52c45b3acf2a
diff --git a/libs/hwui/AssetAtlas.cpp b/libs/hwui/AssetAtlas.cpp
index fddfe90..fc86e4f 100644
--- a/libs/hwui/AssetAtlas.cpp
+++ b/libs/hwui/AssetAtlas.cpp
@@ -28,7 +28,7 @@
 // Lifecycle
 ///////////////////////////////////////////////////////////////////////////////
 
-void AssetAtlas::init(sp<GraphicBuffer> buffer, int* map, int count) {
+void AssetAtlas::init(sp<GraphicBuffer> buffer, int64_t* map, int count) {
     if (mImage) {
         return;
     }
@@ -108,14 +108,19 @@
 /**
  * TODO: This method does not take the rotation flag into account
  */
-void AssetAtlas::createEntries(Caches& caches, int* map, int count) {
+void AssetAtlas::createEntries(Caches& caches, int64_t* map, int count) {
     const float width = float(mTexture->width);
     const float height = float(mTexture->height);
 
     for (int i = 0; i < count; ) {
-        SkBitmap* bitmap = (SkBitmap*) map[i++];
-        int x = map[i++];
-        int y = map[i++];
+        SkBitmap* bitmap = reinterpret_cast<SkBitmap*>(map[i++]);
+        // NOTE: We're converting from 64 bit signed values to 32 bit
+        // signed values. This is guaranteed to be safe because the "x"
+        // and "y" coordinate values are guaranteed to be representable
+        // with 32 bits. The array is 64 bits wide so that it can carry
+        // pointers on 64 bit architectures.
+        const int x = static_cast<int>(map[i++]);
+        const int y = static_cast<int>(map[i++]);
         bool rotated = map[i++] > 0;
 
         // Bitmaps should never be null, we're just extra paranoid