Cleanup: Use SkAutoGraphics in gm and tests.

BUG=None
R=bsalomon@google.com

Review URL: https://codereview.chromium.org/704413002

gm/gmmain.cpp

@@ -2257,7 +2257,7 @@ int tool_main(int argc, char** argv) {
     }
 #endif
 
-    SkGraphics::Init();
+    SkAutoGraphics ag;
 
     setSystemPreferences();
     GMMain gmmain;
@@ -2474,7 +2474,6 @@ int tool_main(int argc, char** argv) {
 
     delete grFactory;
 #endif
-    SkGraphics::Term();
 
     return (reportError) ? -1 : 0;
 }

tests/skia_test.cpp

@@ -127,7 +127,7 @@ int test_main() {
     }
 #endif
 
-    SkGraphics::Init();
+    SkAutoGraphics ag;
 
     {
         SkString header("Skia UnitTests:");
@@ -213,7 +213,6 @@ int test_main() {
         SkDebugf("\nFinished %d tests, %d failures, %d skipped. (%d internal tests)",
                  toRun, failCount, skipCount, reporter.countTests());
     }
-    SkGraphics::Term();
 
     SkDebugf("\n");
     return (failCount == 0) ? 0 : 1;