eliminate all warnings in non-thirdparty code on mac

Most of these issues were due to functions whose definitions appear in header files; I changed those functions to be 'static inline' instead of just 'static' or 'inline', which kills the warning for such functions.

Other functions that were static or anonymous-namespaced but were unused in cpp files were probably called at some point but are no longer; someone who knows more than I do should probably scrub all the functions I either deleted or #if 0'ed out and make sure that the right thing is happening here.

Lots of unused variables removed, and one nasty const issue handled.

There remains a single warning in thirdparty/externals/cityhash/src/city.cc on line 146 related to a signed/unsigned mismatch.  I don't know if we have control over this library so I didn't fix this one, but perhaps someone could do something about that one.

BUG=

Review URL: https://codereview.appspot.com/7067044

git-svn-id: http://skia.googlecode.com/svn/trunk@7051 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/GrDrawTarget.cpp b/src/gpu/GrDrawTarget.cpp
index f80a441..976448d 100644
--- a/src/gpu/GrDrawTarget.cpp
+++ b/src/gpu/GrDrawTarget.cpp
@@ -46,8 +46,13 @@
 }
 
 /**
- * Run this function to generate the code that declares the global masks.
+ * Uncomment and run the gen_globals function to generate 
+ * the code that declares the global masks.
+ *
+ * #if 0'ed out to avoid unused function warning.
  */
+ 
+#if 0
 void gen_globals() {
     GrVertexLayout stageTexCoordMasks[GrDrawState::kNumStages];
     GrVertexLayout texCoordMasks[GrDrawState::kMaxTexCoords];
@@ -66,6 +71,7 @@
     GrPrintf("};\n");
     GrPrintf("GR_STATIC_ASSERT(GrDrawState::kMaxTexCoords == GR_ARRAY_COUNT(gTexCoordMasks));\n");
 }
+#endif
 
 /* These values were generated by the above function */