Add implementations for clipRect(), save() and restore().

The current implementation of clipRect() does not apply local transformations
before setting the new clip.

Change-Id: I5997871bb638dfcd1a8ef96354846af52427e445
diff --git a/libs/hwui/Matrix.cpp b/libs/hwui/Matrix.cpp
index 68b245b..638c1b8 100644
--- a/libs/hwui/Matrix.cpp
+++ b/libs/hwui/Matrix.cpp
@@ -140,10 +140,12 @@
 }
 
 void Matrix4::dump() const {
-	LOGD("%f %f %f %f", mMat[0], mMat[4], mMat[ 8], mMat[12]);
-	LOGD("%f %f %f %f", mMat[1], mMat[5], mMat[ 9], mMat[13]);
-	LOGD("%f %f %f %f", mMat[2], mMat[6], mMat[10], mMat[14]);
-	LOGD("%f %f %f %f", mMat[3], mMat[7], mMat[11], mMat[15]);
+	LOGD("Matrix4[");
+	LOGD("  %f %f %f %f", mMat[0], mMat[4], mMat[ 8], mMat[12]);
+	LOGD("  %f %f %f %f", mMat[1], mMat[5], mMat[ 9], mMat[13]);
+	LOGD("  %f %f %f %f", mMat[2], mMat[6], mMat[10], mMat[14]);
+	LOGD("  %f %f %f %f", mMat[3], mMat[7], mMat[11], mMat[15]);
+	LOGD("]");
 }
 
 };