veyron.go.core: Make context.T a concrete type.

Change-Id: I1f4ce09c8a302214e13da6939a20dbf625d31511
MultiPart: 1/6
diff --git a/tools/debug/impl.go b/tools/debug/impl.go
index a37355a..41f2461 100644
--- a/tools/debug/impl.go
+++ b/tools/debug/impl.go
@@ -73,7 +73,7 @@
 `,
 }
 
-func doFetchTrace(ctx context.T, wg *sync.WaitGroup, client vtracesvc.StoreClientStub,
+func doFetchTrace(ctx *context.T, wg *sync.WaitGroup, client vtracesvc.StoreClientStub,
 	id uniqueid.ID, traces chan *vtrace.TraceRecord, errors chan error) {
 	defer wg.Done()
 
@@ -176,7 +176,7 @@
 // doGlobs calls Glob on multiple patterns in parallel and sends all the results
 // on the results channel and all the errors on the errors channel. It closes
 // the results channel when all the results have been sent.
-func doGlobs(ctx context.T, patterns []string, results chan<- naming.MountEntry, errors chan<- error) {
+func doGlobs(ctx *context.T, patterns []string, results chan<- naming.MountEntry, errors chan<- error) {
 	var wg sync.WaitGroup
 	wg.Add(len(patterns))
 	for _, p := range patterns {
@@ -188,7 +188,7 @@
 	}()
 }
 
-func doGlob(ctx context.T, pattern string, results chan<- naming.MountEntry, errors chan<- error, wg *sync.WaitGroup) {
+func doGlob(ctx *context.T, pattern string, results chan<- naming.MountEntry, errors chan<- error, wg *sync.WaitGroup) {
 	defer wg.Done()
 	ctx, cancel := ctx.WithTimeout(time.Minute)
 	defer cancel()
@@ -317,7 +317,7 @@
 	}
 }
 
-func doValue(ctx context.T, name string, output chan<- string, errors chan<- error, wg *sync.WaitGroup) {
+func doValue(ctx *context.T, name string, output chan<- string, errors chan<- error, wg *sync.WaitGroup) {
 	defer wg.Done()
 	ctx, cancel := ctx.WithTimeout(time.Minute)
 	defer cancel()
@@ -372,7 +372,7 @@
 	}
 }
 
-func doWatch(ctx context.T, pattern string, results chan<- string, errors chan<- error, wg *sync.WaitGroup) {
+func doWatch(ctx *context.T, pattern string, results chan<- string, errors chan<- error, wg *sync.WaitGroup) {
 	defer wg.Done()
 	root, globPattern := naming.SplitAddressName(pattern)
 	g, err := glob.Parse(globPattern)