gopls/internal/lsp/source: rename FileHandle.Read to Content

It does not call the read(2) system call.
This has confused us too many times.

Change-Id: I2bd14aff70e8608ba6254f43c9ccb3bd80618b0b
Reviewed-on: https://go-review.googlesource.com/c/tools/+/474095
Run-TryBot: Alan Donovan <adonovan@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
diff --git a/gopls/internal/lsp/source/completion/completion.go b/gopls/internal/lsp/source/completion/completion.go
index 879312c..c49b3b1 100644
--- a/gopls/internal/lsp/source/completion/completion.go
+++ b/gopls/internal/lsp/source/completion/completion.go
@@ -1215,7 +1215,7 @@
 		if err != nil {
 			return err
 		}
-		content, err := fh.Read()
+		content, err := fh.Content()
 		if err != nil {
 			return err
 		}
diff --git a/gopls/internal/lsp/source/definition.go b/gopls/internal/lsp/source/definition.go
index cb87eb0..b173145 100644
--- a/gopls/internal/lsp/source/definition.go
+++ b/gopls/internal/lsp/source/definition.go
@@ -220,7 +220,7 @@
 	if err != nil {
 		return protocol.Location{}, err
 	}
-	content, err := fh.Read()
+	content, err := fh.Content()
 	if err != nil {
 		return protocol.Location{}, err
 	}
diff --git a/gopls/internal/lsp/source/fix.go b/gopls/internal/lsp/source/fix.go
index 2ed55c4..0559858 100644
--- a/gopls/internal/lsp/source/fix.go
+++ b/gopls/internal/lsp/source/fix.go
@@ -116,7 +116,7 @@
 			}
 			editsPerFile[fh.URI()] = te
 		}
-		content, err := fh.Read()
+		content, err := fh.Content()
 		if err != nil {
 			return nil, err
 		}
diff --git a/gopls/internal/lsp/source/format.go b/gopls/internal/lsp/source/format.go
index b8206ed..e504705 100644
--- a/gopls/internal/lsp/source/format.go
+++ b/gopls/internal/lsp/source/format.go
@@ -91,7 +91,7 @@
 	_, done := event.Start(ctx, "source.formatSource")
 	defer done()
 
-	data, err := fh.Read()
+	data, err := fh.Content()
 	if err != nil {
 		return nil, err
 	}
diff --git a/gopls/internal/lsp/source/implementation.go b/gopls/internal/lsp/source/implementation.go
index 72ec90d..179fc61 100644
--- a/gopls/internal/lsp/source/implementation.go
+++ b/gopls/internal/lsp/source/implementation.go
@@ -231,7 +231,7 @@
 	if err != nil {
 		return protocol.Location{}, err // cancelled, perhaps
 	}
-	content, err := fh.Read()
+	content, err := fh.Content()
 	if err != nil {
 		return protocol.Location{}, err // nonexistent or deleted ("can't happen")
 	}
diff --git a/gopls/internal/lsp/source/known_packages.go b/gopls/internal/lsp/source/known_packages.go
index 07b4c30..ba4e9dc 100644
--- a/gopls/internal/lsp/source/known_packages.go
+++ b/gopls/internal/lsp/source/known_packages.go
@@ -40,7 +40,7 @@
 
 	// Parse the file's imports so we can compute which
 	// PackagePaths are imported by this specific file.
-	src, err := fh.Read()
+	src, err := fh.Content()
 	if err != nil {
 		return nil, err
 	}
diff --git a/gopls/internal/lsp/source/rename.go b/gopls/internal/lsp/source/rename.go
index c67f15c..9bf05e4 100644
--- a/gopls/internal/lsp/source/rename.go
+++ b/gopls/internal/lsp/source/rename.go
@@ -275,7 +275,7 @@
 		if err != nil {
 			return nil, false, err
 		}
-		data, err := fh.Read()
+		data, err := fh.Content()
 		if err != nil {
 			return nil, false, err
 		}
diff --git a/gopls/internal/lsp/source/view.go b/gopls/internal/lsp/source/view.go
index 41bcbac..f81e4cc 100644
--- a/gopls/internal/lsp/source/view.go
+++ b/gopls/internal/lsp/source/view.go
@@ -626,9 +626,9 @@
 	// Version returns the file version, as defined by the LSP client.
 	// For on-disk file handles, Version returns 0.
 	Version() int32
-	// Read reads the contents of a file.
+	// Content returns the contents of a file.
 	// If the file is not available, returns a nil slice and an error.
-	Read() ([]byte, error)
+	Content() ([]byte, error)
 }
 
 // A Hash is a cryptographic digest of the contents of a file.