Change old PRG to be SkLCGRandom; change new one to SkRandom

The goal here is to get people to start using the new random number
generator, while leaving the old one in place so we don't have to 
rebaseline GMs.

R=reed@google.com, bsalomon@google.com

Author: jvanverth@google.com

Review URL: https://chromiumcodereview.appspot.com/23576015

git-svn-id: http://skia.googlecode.com/svn/trunk@11169 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/tests/PictureTest.cpp b/tests/PictureTest.cpp
index 349560b..a42112d 100644
--- a/tests/PictureTest.cpp
+++ b/tests/PictureTest.cpp
@@ -75,7 +75,7 @@
     return pic;
 }
 
-static void rand_rect(SkRect* rect, SkMWCRandom& rand, SkScalar W, SkScalar H) {
+static void rand_rect(SkRect* rect, SkRandom& rand, SkScalar W, SkScalar H) {
     rect->fLeft   = rand.nextRangeScalar(-W, 2*W);
     rect->fTop    = rand.nextRangeScalar(-H, 2*H);
     rect->fRight  = rect->fLeft + rand.nextRangeScalar(0, W);
@@ -178,7 +178,7 @@
         drawbitmap_proc, drawbitmaprect_proc, drawshader_proc
     };
 
-    SkMWCRandom rand;
+    SkRandom rand;
     for (size_t k = 0; k < SK_ARRAY_COUNT(procs); ++k) {
         SkAutoTUnref<SkPicture> pic(record_bitmaps(bm, pos, N, procs[k]));
 
@@ -263,7 +263,7 @@
 }
 #endif
 
-static void rand_op(SkCanvas* canvas, SkMWCRandom& rand) {
+static void rand_op(SkCanvas* canvas, SkRandom& rand) {
     SkPaint paint;
     SkRect rect = SkRect::MakeWH(50, 50);
 
@@ -284,10 +284,10 @@
 }
 
 static void test_peephole() {
-    SkMWCRandom rand;
+    SkRandom rand;
 
     for (int j = 0; j < 100; j++) {
-        SkMWCRandom rand2(rand); // remember the seed
+        SkRandom rand2(rand); // remember the seed
 
         SkPicture picture;
         SkCanvas* canvas = picture.beginRecording(100, 100);